Edtechteacher has compiled a great library of annotated web resources for ancient history,ancient Greece, and Rome. They are terrific!
For example, you'll find a link to a great British Museum site for ancient Greece which is ideal for a student web-quest. On Edtec's ancient history page, you'll find a link to the Evansville University page, Exploring World Cultures which includes pages on India, China, Islam, Egypt and Europe with primary sources, essays and images.
This site is definitely worth bookmarking.