Best Places to Start

American Factfinder 2

This is the U.S. Census Bureau's main portal to demographic and economic data, including the Decennial Census, Economic Census, American Community Survey and more.

DATA.GOV

DATA.Gov is a search engine for "machine-readable" datasets collected across all federal executive agencies. It provides access to compiled data and raw datsets.

Bureau of Labor Statistics

The Bureau of Labor Statistics tracks the Consumer Price Index (CPI); labor and employment statistics (unemployment); and wages, including occupational information.