I have a level 98 Paladin, and have tested a variety of skill & gear setups. There are 2 different ways to go about gearing this class. One can run with a Mageadin by using mostly equipment with bonuses geared toward casting as well as a 1h + shield. From the other side there would be a Meleeadin, which will use something like plate armor, or anything geared toward attack speed or increasing physical damage, and then use a strong 2h weapon. All things considered, and if you have access to all the gear in the game, the Meleeadin setup does more DPS, but the Mageadin setup is more tanky due to having a shield. This makes gearing up a Paladin not that difficult, because you can mix and match tons of different pieces and get beneficial bonuses. Oh and the crusader set in its entirety is garbage, don't use it. The best 2 pieces are the shield and the amulet IMO.

If you want to see what end game gear looks like, then click the Paladin in my sig.

FYI, I didn't come up the the "meleeadin" build as far as using warrior's set + staff of sentoth. I believe that was originally Tezz who came up with it. So yeah, I kinda stole that gear setup. Sometimes I'll see what others are using and compare it to what I came up with. Sometimes my setups are better, other times not. My original setup I came up with was a Mageadin using a combo of Sorcerer's and Warlock's set w/crusader shield. Its about 6k less DPS than the Meleeadin build I'm using now.

The 3 core skills I recommend getting to level 20 are:

#1 - Vengeance - Holy light strikes random targets 12 times. Make sure this is the first skill you get to level 20. With a Mageadin setup using top tier end game equipment (I used a combo of sorcerer's and warlock's set w/crusader shield), these can crit for as much as 14k damage per hit.
#2 - Rebuke - Lightning strikes 5 targets. Keep in mind this doesn't mean it will hit each target if there are 5 on the screen, the hits can be random, and 1 target might get hit 2-3 times, or if there is just 1 target, then all 5 strikes will hit that one target.
#3 - Valor - Maxing this out will counter mob attacks with a lightning strike, which I believe is physical damage? Anyway, this attack does more damage on a Meleeadin than on a Mageadin. I've seen it crit for 6500+ damage, and if you're 5 pulling mobs on nightmare and hell, you'll be seeing lots of these fly across the screen.

Other notable skills:

- Greater healing - This enchants weapon with arcane damage. Its not worth it on a Mageadin, but its worth getting on a Meleeadin. The arcane damage seems % based, and isn't a flat amount.
- Yaulp - The magic bubble effect isn't all that great, but this is a good skill to level to 20 anyway just for the damage bonus. As a 4th or a 5th level 20 skill, this is a good choice.
- Holy Might - depending on your setup, +40% more damage vs stunned targets might be good. Its definitely not a useless skill, but this would be a 5th skill choice in pretty much any build I'd even consider getting this skill for. If you're lacking DPS, this might help you take out champs/bosses easier.

Here is a chain I did with my level 98 "Meleeadin"

My sustained DPS is usually 18k which I can maintain during a chain of about 300-400.