searched istockphoto for a 2011 infiniti picture, found nothing *cries*
eVox and izmostock are the only two games in town that picture all makes/models as far as I know. Both of their websites are horrible to see if they have updated images, obviously so people don't steal the latest models
Shutterstock and iStockPhoto are decent for general interest photos. Flickr might be your best bet for sheer number of topics. And you would probably have to take the added step of contacting the owner of the photo and negotiating a price. Takes the stock out of stock photo!