(Photo of the Birmingham Campaign by Marion S. Trikosko for U.S.News & World Report, 15 May 1963.)
Some of the manuscripts and photographs created by workers in the Federal Writers' Project interviews with former slaves are available on the Library of Congress website.
Approximately 60 audio file interviews of former slaves, many of them women, are also available.
The United States releases tremendous amounts of statistical data, broken down demographically. Some of the best sites include:
FRED (Federal Reserve Economic Data)