Catalog of U.S. Federal data sets and spatial data. Future funding for this source is uncertain.

Historical Census Data Browser of the University of Virginia, Geospatial and Statistical Data Center provides access to summary level data collected by the U.S. Census from 1790 to 1960. Database generates longitudinal tables and maps.

Provides, free of charge, aggregate census data and GIS-compatible boundary files for the United States between 1790 and 2000.

Microdata files of representative samples drawn from the Census and American Community Survey from 1850 to the present.

Interactive database provides ready access to Census statistics about population and housing, at local, state, and national levels. Note "legacy" versus 2010 version.

Social Explorer allows users to create maps and generate reports based on demographic data from the United States Census. Note: free and subscription versions available. Data from NHGIS (see link below).

Based on ACS 2005-09.

Free! Thursday, June 9, 2011 from 12:00 – 1:00 p.m. (EDT). See link for more information and to register.