There is an excellent resource for information, photos, audio, video, and more related to American History and the American Experience. Developed by the Library of Congress, this site is rich in content. You can browse a collection or specify keywords and topics.

American Memory from the Library of Congress - Home Page (http://memory.loc.gov/ammem/index.html)

Yes, and excellent resource. I access it for something about once a month. Definitely on my top 10 reference sites on the net.