When you turn the key to start the car, does it make one click and then the lights go dead? If so it could be the wire that runs from the positive battery terminal to your starter is loose or corroded, happened to a few people i know including myself twice... just check to see if the wire is loose or corroded, clean it off or cut down the wire to get fresh wire and tighten up the terminal thing as much as you can. If this fails then yeh go buy a new starter... Always try to save the expensive choices for last.