I think we need more details - how many coats of paint are currently on the car? What else in terms of body work is needed? Are you planning a color change? And most of all, what are your intentions, driver or show?? And then there is always $$$ to consider.
You might want to spend some time at http:/www.autobodystore.com IMHO the best auto paint group on the web.
If you've got good paint on there already, and there is no bodywork needed (Dents, waves, chips, etc), you can do it all yourself.
First is removing all of the emblems, lights, etc from the body. Then buy a long block and some 400 and 600 grit sandpaper. Make sure it is Wet or Dry paper, so you can wet sand. I'd fill a spray bottle with some dish soap and water, and sand the whole car with the 400 first, then with the 600. The soapy water gets any grease or wax off the car, and keeps the sandpaper clean as you go.
ANY bare metal spots will need a quick coat of primer, then wet sand the spot with the 400 and 600 paper.
I did my first car like this, and it came out pretty good.
I would recommend going a step further, especially for a daily driver car, though. I would get some 180 and 220 grit paper, and sand the existing paint with those first. This gets most of the old paint off without going to the bare metal. After the 220, primer the whole car with a good primer-sealer. After this is dry, wet sand with the 400 and 600 grits.
has one coat of paint from 3 yrs ago. body work is fine mainly wondering what to rough it up for better adhesion.. have added on some fiberglass pieces ground effects hood scoop ect so i now have to repaint so i figured i would just spray the whole car