Class Information and Resources
 

Generic Class Resources:

Elitist Jerks is not only the home to the Elitist Jerks guild, but its forums also contain some of the best theorycrafting for the game. There is a section for each class with guides on talent specs, gems, etc.
http://elitistjerks.com/

Noxxic has information on both PvE and PvP for all classes. There are also gameplay guides on macros, keybinds, addons, etc.
http://www.noxxic.com/

Rawr is a downloadable program to compare gear and find possible upgrades. It supports most classes and specs, a list of which may be found on their website. You can import your character either from the Armory or by a companion addon.
http://rawr.codeplex.com/

Simulationcraft is a downloadable program that simulates WoW combat mechanics to provide detailed information about your DPS.
http://www.simulationcraft.org/

WoW Popular tracks the most popular talent specs, gear, etc. used by the WoW population found by scanning both the US and EU armories.
http://www.wowpopular.com/


Death Knight Resources:

Son of a Lich is based around DPS Death Knights, both Frost and Unholy specs.
http://sonofalich.com/


Druid Resources:

Mew is a downloadable program written to simulate the DPS of Cat Druids. It calls the Elitist Jerks' forum its home.
http://elitistjerks.com/f73/t110356-...mew_simulator/


Hunter Resources:

Female Dwarf is a web-based hunter DPS analyzer.
http://www.femaledwarf.com/

Petopia is dedicated to the tamable creatures of World of Warcraft. The site is full of guides on taming and caring for your pets, talents and skills for every pet, and has a browsable database of all possible pets in the game.
http://www.wow-petopia.com/

Warcraft Hunters Union is a blog dedicated to hunters with articles on talents, pets, and gameplay.
http://www.warcrafthuntersunion.com/


Rogue Resources:

Shadowcraft focuses on the optimization of a Rogue's gear, reforges, and talents and shows expected dps.
http://shadowcraft.mmo-mumble.com/

Shadowpanther is a site dedicated to all things Rogue for both PvP and PvE including guides on power-leveling, twinks, and which professions to take.
http://shadowpanther.net/



I'm sure that there is more that can be added to this list. If you have come across a site in your WoW travels that you think should be listed here, send me a PM on the site.