>Anyone ever written a vin number decoder? I found some code that will give me a checksum and the year of the vehicle, but can't seem to find anything that definitively gives me make, model, body style and color.

Just a few...

http://www.vehicleidentificationnumber.com/vehicle_identification_numbers_vin_detail.html
http://en.wikipedia.org/wiki/Vehicle_identification_number

These came from Google

Somewhere around this office we have a more descriptive white paper.