You might checkout this route.
http://www.automotivetouchup.com/ I just repainted a front and rear bumper on my 10 GTI - my first time painting something like that before that I've only done wheels with a rattle can...
I used their "ready to spray" paint with my HPLV paint gun and their aerosol can products and both have been good. they have been VERY good on the color match on my CSG bumper. I didn't like their standard clearcoat, so I'm trying their 2K Urethane Clearcoat as its supposed to be much more stable & durable - but its nasty stuff - like cancer causing stuff. So, I'll be more careful with the respirator...
from what I understand the process of painting plastic is a LITTLE different than painting metal surfaces. The damage you have looks down to the plastic, so you'll need a plastic adhesion promoter to get paint to stick to it. the prep is the #1 most important step IMHO.
word of advise - don't go too crazy with the sanding & primer - the more you sand off and prime over, the more you have to paint back on... and when it says to scuff up the paint, scuff it up, not sand it off
They have some good short tutorials:
http://www.automotivetouchup.com/how-to-videos/
http://www.automotivetouchup.com/directions.htm
the process isn't too terribly difficult...
