I too am a DIYer and hate to pay someone to do something that I
think I can do myself (last week replaced my gas furnace with a new one I bought on Ebay).
Painted my bumperettes and a bumper cover for my F-150 from paint I got from automotivetouchup.com. Also painted my kid's fender panel. Other posters are correct; you are not a professional painter, don't have pro tools, or a paint booth. But I think you can achieve good results. Check out the video on their site where they refinish a bumper here:
Bumper Repaint Job | Touch Up Paint | AutomotiveTouchup
Yes, they make it look easier than it really is and left out a couple of finishing steps. A few things to keep in mind. Get the plastic adhesion promotor and get the little gun that clips on to the spray can. I like to get close to the work, so I also got their respirator - the fumes are very strong. Also, to get a good gloss finish, it took some effort with some very fine wet/dry sandpaper and light rubbing compound.
My painted bumperettes thread is here: http://986forum.com/forums/general-discussions/30418-4-hours-$50-later.html
Color matched materials will run about $100. Good luck!