We have posted an archive of the TIGER/Line 2006 Second Edition files at http://www.vrdc.cornell.edu/tiger/. These are public-use data files as published by the U.S. Census Bureau's geography division. These files are provided as a convenience for the community, since they were used in the creation of geographic definitions for public-use files available on this site
The files archived here stem from http://www.census.gov/geo/www/tiger/tiger2006se/tgr2006se.html. While the files are still available as of Nov 2008, the copy on this site ensures that they will remain should the download site at Census remove them. For a more complete archive, consult TIGER/Line Files @ ICPSR.
Note: the original posting from October 31, 2008, referred to the "First Edition" of the 2006 Tiger files. This was corrected to refer to "Second Edition" files as of November 10, 2008.