I had a graphic printed for my wifes Freelander wheel cover by a local company. He used my digital photo and produced a very reasonably priced large graphic. He is now thinking of doing them as part of his business. He is happy to do one-offs and just requires a high res digital photo (preferably 300 dpi for best results, although once on the car, even a 72 looks OK).
You can contact him at:
screenpromini@aol.com
for a quote.
Please let him know Steve Nash forwarded you to him and he will offer his best price.