Hi robotninja, cars tend to be a pretty high level of difficulty and will likely take a fair amount of time invested to get going with them. But here are some links that may be useful:

http://moi3d.com/forum/index.php?webtag=MOI&msg=2687.1
http://moi3d.com/forum/index.php?webtag=MOI&msg=2546.1
http://moi3d.com/forum/index.php?webtag=MOI&msg=1267.16
http://moi3d.com/forum/index.php?webtag=MOI&msg=898.2
http://moi3d.com/forum/index.php?webtag=MOI&msg=1749.1

http://www.suurland.com/
http://www.carbodydesign.com/ (try the 3D Tutorials section, in the Rhino section).

- Michael