I just used a black/white gingham paper for background. Then I backed all my son's photo with black mounting paper. The black/white theme worked because my son took a picture with the checker-flag girl.
for design, I just bought cars diecut, then I cut out larger circles for the tires because it was a Monster Truck Show page. I used glue dots to stick the tires on because I wanted the 3-D effect.
I've seen some Nascar stickers at Michael's too. You might want to try them!