Welcome to the board,
What type of damage do you have? Cracks, Rash, Scratches, where is the damage...
For the LOW BUDGET:
Most of the time you can repair a crack with JB WELD, Plastic Welding, Fiberglass etc... and cover it up with a sticker or touch-up paint
Rash is harder to cover up, depending on how big the rash is you'll have to sand it down and repaint the whole plastic... If its small enough you may be able to get away with touch up paint.
If its just scratched you can usually buff them out with compound.
If you have pics that would be cool to help you better.
For the HIGH BUDGET:
AUTO BODY SHOP and CUSTOM PAINT JOB =)