Planet Age of Empires - Community site, with game data, reference information, downloads, news, forums, and tournaments. - http://planetageofempires.gamespy.com/
FilePlanet - File downloads including scenarios and utilities. - http://www.fileplanet.com/54207/0/section/Age-of-Empires-Series
Age of Empires World - Offers screenshots, information, and links. - http://www.ageofempires.iwarp.com/
Nahoo - Features scenario and campaign downloads, quizzes, and cheats. Also has a forum. - http://nahoo.net/games/aoe/
Age of Empires Heaven - Offers a collection of articles and game downloads. Features campaigns and scenarios, patches, utilities and add-ons, map information, an FAQ, interviews, and game history. - http://aoe.heavengames.com/