Here are 2 websites that have car patterns: http://cyberstitchers.com/PatternLibrary/index.asp?_perPg=10&_cols=1&navPage=8 scroll to vehicles, these are a free download. http://www.Crosstitch.com also has 5 or 6, however, you do need to be a member $10.95 US & $12.50 Canadian a year. There are numerous other patterns so the membership is reasonable. Hope this helps.

There are loads of designs of cars and bikes at http://www.stitchtastic.com/default.aspx

I have stitched a few of these and they look great.

Clickable link is below

Here is a link that might be useful: Cars and bike cross stitch