Investigative Reporters and Editors Inc. (IRE), a non-profit organization, has made the 2000 and 2010 U.S. Census data easily available in CSV and JSON formats. From the site census.ire.org you can browse through the census data and export what you need.
You can also find the entire site Github.
Although IRE is clearly focused on making this data available for journalists, it could come in handy for certain types location-based applications.
IRE has more Census-related resources available here.