Found another link to get to where I wanted...
The actual tool is called NextWheels Online. Go to the address below, then click on the "Launch NextWheels Online" button.
http://www.fountaintire.com/custom_w...rtual_wheels/#
Looks like it may have been updated a little since I used it last... the background behind the vehicle is much darker now (you can't see how the window tint looks very well).