A really good way to figure this out would be to go to the mall! Go to a department store like Kauffmans, Lazarus, or Macy's. Then find their makeup counters (MAC and Clinique are both good). Tell the ladies there, just what you told us and they will help you to find the appropriate colors and also show you how to apply everything. They will usually put some on you right there! In fact, I was just at the Clinique counter in Macy's yesterday having them find the right shade of foundation because I had got some sun over the last week and now mine is too light. It's much easier this way because you can have someone else making sure the colors are just right. If you find that their makeup is too expensive, you can at least get some tips and advice from them. They will still show you everything. Then you can go to the grocery store a bit more prepared to get some cheaper stuff.
Another idea is to buy some various cheap brands. Colors that you like and think might look good. Experiment with them at home and take pictures of yourself with either a polaroid or a digital camera. For some reason, looking at yourself in a picture is very different then looking at yourself in a mirror. Or maybe it's just me being wierd? Haha!