Paladin Guide on WoW Forums -
This is an awesome guide on the paladin class in general.

Geld's Paladin Guide -
This is another guide from WoW Forums, almost the same content but I think this one is more elaborate.

Paladin Blog -
Very informative Paladin Blog that has guides on many subjects.

Paladin Guide from Ten Ton Hammer -
A general guide on paladins, great guide to look at if you are considering leveling a paladin.

Paladin Talent Guide -
Great talent guide from EU forums, has many builds with links to examples. Updated for TBC!

Spell Damage Coefficient Guide -
Ever wonder how much +spell damage your spells are actually using? This is a great post that shows you exactly how much your spells are being improved.

Paladin Tanking Guide -
If you want to be formidable tank for your groups this guide is for you. Lots of information on how to keep aggro and what seal/judges you should be using.

Healbot Pre-Raid Equip Guide -
Guildies making you go healbot for the future raids? This guide covers all the TBC +heal items you should get before raiding.

Blood Knight Charger Guide -
How to Get Charger -
Having trouble or wondering how to get a Blood Knight Charger for your Blood Elf? These guides shows you which quests to complete and what reagents you need to buy/farm.

Expansion Paladin Leveling Guide -
Decided to roll paladin for the expansion? This guide is just for you. Short but has the information you need while leveling up. Talent Point Placement/Weapon Guide/Strategies etc.

Paladin Sets for TBC -
Short Guide on which Armor Sets you should be shooting for during End-Game.

Paladin Pre-Raid Gear Guide -
Another Guide on which gear you should be trying get before raiding.