How much would a 1978 Pontiac Trans Am be in okay condition?

I am looking for cool older cars and i really like the looks of the 1978 Pontiac Trans Am, and the 1978 Pontiac Firebird. I'm 17 years old so i really want a nicer first car compared to half the other teens who get a peace of crap car. The car doesn't have to be in perfect condition obviously. A little rust would be fine, but not excessive rust. I don't want it to look like a junker. I want it to look at least somewhat nice you know? How much would a car in this kind of condition cost at a fairly good price?