This is the main list and incorporates all URLs from the posts below so no need to scroll down
Official WoW European Site
QuestKeep - useful for quests
World Of Warcraft Database
World of War.net - everything you need to know about WoW
Thottbot - WoW database
WoW Cartography
Allakhazam - more WoW Resources
Goblin Workshop - Quest Guides etc
Another great WoW site
IGN wow site
Please respond to this thread and I will update the list on the first post. Please put them in the same format i.e. the url with a description of the site