A lot of info about ODB2 can be found on the internets. A diagnostic reader is not really cheap as well.
Here are some fun projects i found;
Here's a guy who builds cables, so you can interface with a laptop. (software downloadable there too)
HackaDay also has an article about a cheap custom reader.
Here's another little application.
Seems that there's something for the
iPhone as well called
'rev' (it interfaces through an WiFi OBD-II dongle,
ooh yeah baby).
This post has been edited by i20: Oct 27 2009, 05:49 PM