A not-half-bad article regarding the assorted 9/11 conspiracy theories wandering about the Internet:

ABCNEWS.com : Some Ask, Were Aliens or Bush Behind 9-11?

Though at first glance it may seem strange that there should still be people looking for Sept. 11 villains besides bin Laden and his al Qaeda network, people who have studied conspiracy theories over the years say it is perfectly natural, and even a fundamental part of the American character.