ALS: Automotive Grade Linux

The easiest solution is obdgpslogger, which has Debian and Ubuntu and (probably still) Fedora packages:

http://icculus.org/obdgpslogger/

I also recommend having a look at mp3car.com forums, scantool.net forums, #linuxice IRC on freenode and (until elinux.org page Nate mentions exists):

http://wiki.openivi.org/index.php?title=Main_Page

http://mikesshop.net/

There were working Ubuntu and Debian packages for nobdy and libobd before the maintainer fell far behind, but I hear she hopes to catch up over Thanksgiving.