photoshop coloring help?

I am trying to color a car in photoshop using the paint tool may be the wrong tool entirely?)

This is what I have so far, never mind the pencil marks areound it. As you see, it is blatantly a poor excuse for "colored in photoshop."

http://img113.imageshack.us/img113/6522/truckfz6.jpg

This is the reference material I am using for the photoshop project:
http://img421.imageshack.us/img421/799/croppednn5.jpg

Does anybody know how to blend those colors together, without using the "blend" tool, or a better way of coloring, besides using 8 colors instead of 4?

Thanks a lot

hi i believe there are lots of tutorials ard regarding coloring, you can find some here or in deviantart. Play ard with airbrush settings