I've definately seen the shit you're talking about on Pimp my Ride and shit like that.

Fuck knows where you'd get it from though.

Frisket or Frisk Film, transparent masking film, compatible with almost all surfaces. Most professional artists use the matte film because it allows spontaneous pencil drawings right on top of the film, and has very light tack.

*edit*
started using this stuff in Airbrush class in highschool.. You can draw (or print) on the surface to get your outline, then you cut it with a razor blade and a steady hand.. remove that section and paint away, you can even put the piece you cut out back and take off another section.. Any art supply store should have it, normally comes in generic canvas sizes.

With egg and you, i'm sure it will pretty damn rad shit.  i've received countless compliments on the skulls yolk1 did on the wagon.