US Census Bureau
U.s. Bureau of the Census: Hispanic Population of the United States
This web-page from the U.S. Bureau of the Census looks at the hispanic population of the United States via census data and other facts.
US Census Bureau
U.s. Census Bureau: Race: Black Population
Links to census data on the black population in the United States.
Other
Demographics/data Bases
This Business Nation site has links to numerous actual demographic databases such as the Bureau of Labor Statistics and the United States Census Bureau. It is a good site to attain actual data on the various demographic categories.