American FactFinder, your source for population, housing, economic and geographic data from Census 2000, 1990 Census, and 1997 Economic Census.
CenStats Databases (no longer updated after 2016), from the Census Bureau. User specifies geographic areas, data sets, commodities, etc. and CenStats finds and displays the specified data. As a value-added enhancement, CenStats takes advantage of a standard feature of the Internet by providing direct links between several databases that have common geography (i.e., counties, ZIP code areas, and census tracts). Covers current Census data as well as current county data, international trade data, and building permits.