African Census Analysis Project is probably the best site to look for African census data. Contains data from many countries from different years. Sign up is required.
Center for Demography and Ecology is a research cooperative for social scientific demographic research.
- National Survey of Family and Households of a national sample of 13,007 participants has cross-section data from three longitudinal surveys (1988-89, 1992-94, 2002-04).
- Wisconsin Longitudinal Study (WLS) is a longitudinal study of 10,317 pariticipants who graduated from Wisconsin high schools in 1957.
Demographic and Health Surveys collects data in developing countries about population, health, and nutrition programs.
Family Life Surveys contain data on Malaysia (1976-77, 1988-89), Indonesia (1993, 1997, 2000), Guatemala (1995), and Bangladesh (1996).
IPUMS International has 158 census samples from 55 countries, going back to the early 1970s for some countries.
Homeland Security offers data on immigration into the U.S.
Migration Information Source provides statistics on international migration.
Population Reference Bureau has population information on important social, economic, and political issues.
- PRB DataFinder is a database where you can obtain international data on these issues.
Table Maker, by the Alan Guttmacher Institute, has data on sexual and reproductive health, education, economics, etc.
World Health Organization Statistical Information System (WHOSIS) has links to worldwide data on health issues.
U.N.Economic and Social Development: Population Programmes has links to many U.N. programs that deal with population issues.
- World Population Prospects gives worldwide data on many subjects, such as migration, fertility, mortality, etc.
U.S. Census Bureau is always a great source for population studies.