Data,census,gov is the major portal to census data from the most recent decennial censuses and the American Community Survey.

The Census Bureau provides this Training Resources Library that contains a number of presentations that cover many of the products available from the Bureau.

Selection of instructional sessions from the North Carolina Library Association's series of webinars for government documents librarians.

STATS America is a service of the Indiana Business Research Center at Indiana University's Kelley School of Business. They collect data from federal and state sources, along with some commercial or private sources. The site provides state and county profiles. Tabs at the top allow you to click through multiple reports.

After picking the geographic area you are interested in (Either state, county,minor civil division (MCD), census tract or census block group) you can choose to view one of a number of demographic reports, regional profiles , or a report from the 2007 Agricultural Census. You can also find data from the 1990 census here. 1990 data is not included in American FactFinder anymore.

The Missouri Census Data Center (MCDC) also provides these reports based on the American Community Survey.

Located at the University of Minnesota, the Minnesota Population Center disseminates demographic information to researchers worldwide. Resources at the Minnesota Population Center include Canadian and British as well as US census data. You can also find interview data and historical GIS boundary files at this site.

The Census.IRE.org site is a cooperative project of a number of journalists. Its mission is to make census data easier to obtain so that more time can be spent analyzing it.

The National Historical Geographic Information System (NHGIS) provides, free of charge, aggregate census data and GIS-compatible boundary files for the United States between 1790 and 2011.