Here's a tip on how and where you can access, for free, the 2009 Census Bureau TIGER/line files in ESRI SHP format

From the Census Bureau:

What are the TIGER/Line Shapefiles?

• May 2009 extracts containing geographic and cartographic information from the Census Bureau's MAF/TIGER^® (Master Address File/Topologically Integrated Geographic Encoding and Referencing) database.
• The files provide the digital map base for a Geographic Information System or mapping software. The files do not contain any mapping software.
• Contain the boundaries for legal entities as of January 1, 2009.
• They include spatial data for geographic features such as roads, railroads, rivers, and lakes, as well as legal and statistical geographic areas that correspond to the 2009 American Community Survey, 2009 Population Estimates, 2007 Economic Census, and Census 2000.
• The geographic entity codes needed to link the Census Bureau's demographic data to the geography are included in the files. The TIGER/Line Shapefiles do not contain any demographic or economic data; data must be downloaded separately.
• Metadata in Extensible Markup Language (XML) format is included with each compressed file.

Download

• Download the 2009 TIGER/Line Shapefiles now.

Technical Documentation

• Access complete technical documentation, user notes, and a description of the organizational structure of the files.

Frequently Asked Questions

• Frequently asked questions about TIGER/Line Shapefiles.