woodz's rewrite of his guide has inspired me to finish my own. feel free to post suggestions on improvements. some info about my experience; i've been playing this build for well over a year now. i've remade my hammerdin several times and while i havent tried everything that i possibly could, i have dabbled with skill placement and gear enough that i feel i'll hit the high points. this guide is written from the perspective of East Ladder, if you're NL and cannot get a couple spirits, you're on your own for gear selection though much of it will be the same. also i believe Europe goes to lvl 29 instead of 30 for their duelers. if that's the case then you'll look for +1 pally ammy and circlet instead of +2 combat. all other gear should be nearly identicle unless they have some other standards i've not heard about.
low level dueling (lld) like high level dueling (hld) isnt cheap. however, an overall "good" character can be started and be very effective in public duel games with fairly inexpensive gear. that's what first attracted me to lld. you can hold your own with gear you find or trade pgems/mid runes to get. tricking out your character will take a lot of time, effort, and hrs just like hld.
there are several possible combinations of gear and skill placements, but stats are pretty much generic so i'll start with those.
str: enough for gear. it should be either 45 for mages, 50 for eth frosties, 60 for non eth frosties, or enough for whatever pole you're using if you decide to use one.
dex: if you're going to be pubing it up or plan on dueling in a league that has chargers and bowazons, get max block with holy shield. if plan on only dueling casters then you can skip the dex as well as the holy shield.
vit: all the rest
paladins have many things going for them in pvp, one is they get 3 life per vitality spent. another is holy shield making max block easy to hit even with a low blocking shield such as spirit. with that in mind you should aim for 850+ life after charms and gear are taken into account. over 1000 life isnt hard to hit, however so shoot for that. mana is very gear dependent, but when you're dueling with good people your duels will last longer and to keep charging and spamming hammers you need as much as you can get. 500+ mana is a good starting point, but you should aim for 700 or more.
what you need is as many +skills as you can get. try to save stat points wherever possible by getting them on gear. res isnt as big a deal on a pally as it is on other builds because you can make spirit in a pally shield with resists. i dont recommend any other fcr bp other than 125%. someone on a budget will be able to get 125% easily since you probably wont be using sojs right off the bat and the pro will have acces to a 20fcr circlet. you dont need to worry about fhr at all with 2x spirits since 110 is way over the 86% bp and the next one is 200 and not worth shooting for.
hat: peasant crown, not much can top this, if you're on a budget and cant get this for pgems try tarnhelm or lore. if you have either of those though you can trade for a pcrown.
ammy: eye of etlich, telling of beads, or 1pally/mods
weapon: spirit sword (low reqs are alright, but if you opt for a high damage pole insight on switch you may as well use a higher req one, i recommend battle sword)
armor: vipermagi (spirit shroud and stealth are good alternatives, but if you're not picky then a low viper should be cheap)
shield: spirit in a 30+res pally shield (try to get one that has str req comparable to the rest of your gear. if you use mage fists 45 str will be your heaviest item and therefore a heraldic is your best str:block ratio shield)
gloves: magefists (if you dont need the fcr then frostburns are what i'd use. bloodfists and sanders have life but you'll need mana more)
rings: 10fcr rings (good mods are more mana, life, res, and stats)
belt: string of ears is the go to belt here any stats will do 15%dr/15mdr is perfect (other perfectly good options are nightsmoke (mana, res, damage to mana), deaths (if you feel you need it. note: being frozen doesnt slow down your primary means of movement, charge so cbf is something you can do without), also a good rare can be nice but would wind up being harder to find and more expensive than a simple string of ears).
boots: sanders are easy to find and cheap. alternatives are ck boots (more stats), good tri res boots (really shouldnt need the resists), or crafted blood boots with 10 life replen/20life and other good mods. if you're going for the maximum damage hammers can produce as you can then you should use tearhaunch.
switch: when i first started i used an insight in a partizan it made fast work via charge of many pub idiots. i then switched to rune staff insight for the lower req and therefore more life. another option is a foh/convic scepter + spirit you're then considered a mage. i've run in to a couple hammerdins that use a scepter with +meditation coupled with another spirit. this allows them to regenerate mana and still be able to block arrows as well as gives you that absorb from spirit vs bone necs while you're regenerating mana (it's a small amount but every little bit helps). i have never personally tried this, but i thought i should include it for completeness sake. another possible switch is a +holy shield scepter which would save you a skill point into it.
Starter gear set up:
eye of etlich
spirit crystal sword
spirit heraldic shield
2x fcr ring
string of ears
switch insight in whatever
put pskulls in helm and armor. if you find your duels lasting less than 2 min then sub in prubies but at around the two min mark a skull will have replenished your life more than a ruby adds to your base life (assuming you're not at full life for that two minutes. it also regenerates mana as well. stash is filled with as many life/man charms of any size as you can fit. dont use stat charms (str or dex) as they will paint you into a corner and as you slowly get better charms you'll have to remake your character just because you had a 2 str sc.
as long as your spirits add up to 55% fcr, you have the 125% bp.
Advanced gear set up:
2pcombat/20fcr/life/mana circlet socketed with a pskull
33%/100+mana spirit long sword
35/13 vipermagi socketed with pskull
33%/100+mana/45res aerin shield
frostburns (eth if you can to save 10 str)
15%/15mdr string of ears
cow kings boots (for vs melee then 10replen/20life blood boots vs casters)
stash filled with 40x 15life/mana scs. depending on how many stats you place and your charm quality you will have well over 1k life. my current hammerdin has 1213 life with max block.
make sure your spirits add up to 65% fcr then you're hitting 125%
there are a couple ways to go with this build. i'm assuming and recommending you get hell rushed. i have a norm only character that can see games for me. if you dont want to go to the trouble you can do just fine on a normal only rushed pally, just take 8 skills away from a synergy. alternately you could just make games instead of trying to see ones already in progress. this also allows you to set any level restrictions you want.
1 prayer, defiance, clense
13 vigor (i choose to max vigor over blessed aim as i tend to charge idiots w/o block and the extra damage for charge is easy enough to get here)
6 blessed aim
1 conc (only half the listed damage increase gets added to hammers so no more than one point goes into conc. blessed aim and vigor add more damage).
1smite, charge, holy shield, holy bolt
13 blessed hammer (maxed for the lvl)
with this skill placement and either of the gear selections i mentioned you'll be doing 1.4-1.6 k hammer damage.
i dont recommend going without vigor. you may think that putting the points you'd put into it into BA/conc would get you greater hammer damage and you'd be right, but not having vigor makes basic desync more difficult. oh since i brought it up desync; it happens. it's not bm (in fact i've had fewer people complain about it in lld than in hld). it takes a lot of practice to do it on command and requires more skill to master than teleporting around. it's the way a paladin gets around, it can be countered with basic knowledge of it and so i dont see it as bm. other people disagree, but if desync didnt exist at all, i'd still use charge to move around.
that being said there is a way to get around placing skills in vigor and that is the unique tearhaunch greaves. i've not personally used them as i see the 70 str req and low amount of useful stats as not being worth the amount of life you lose nor the smattering of hammer damage you gain. my first hammerdin didnt have vigor (nor did i use tearhaunch) i've long since become a vigor addict and i'm listing these from memory and math.
19 blessed aim
4 conc (this time you're going to dump the rest of the points into conc since you've maxed the only synergy you can.)
1smite, charge, holy shield, holy bolt
13 blessed hammer (maxed for the lvl)
i believe that 1.8-1.9k hammer damage is what this one works out to be (feel free to correct me if i'm wrong). if you want to further increase your damage you can either skip holy shield or get it off of a scepter thereby saving yourself a point that you could then place in conc.
Strategy and matchups:
as in many other guides i've read i'm only going to hit on the basics. desync takes tons of practice and i still dont believe i've mastered it as well as many i've faced. charge around with vigor on, switch to hammer/concentration and make some hammers, switch back charge/vigor, switch... rinse wash repeat. the difficulty is knowing when you're most likely desynced and knowing what kind of patterns to use vs various builds and when to not use a discernible pattern. during long duels whenever you get a breather or need to regen mana switch to insight and put clense on (assuming you have it). you'll regen your mana very fast and the clense will replen your life as well.
pretty much anything with a decent amount of frw and a ranged attack (especially the homing attacks). skill of the opponent plays a huge factor. tough matchups include; bowazon, bone mancer, light trapper, poison zon. if they run around dont complain, they have to dodge invisible hammers so learn to get ahead of them and try to predict their movements (for the open field ones like the zons). bone mancers are probably the toughest to duel vs if they know how to use bone walls to funnel you and also when to run out of the area away from you.
edit: forgot to give thanks to all the guys i've dueled with and learned from, destructionjoe (wouldnt have known any of this without his guide), woodzman, pallyanderson, smitty, junkie, cokey, and many others i've forgotten (sorry). big thanks to unkie mike for being a good mod even if you are going senile.