I didn't think it was possible to find a Mustang for under $5K, but your post intrigued me so I looked at my local dealership (Raceway Ford in Riverside, CA
) and found a decent looking 2002 Ford Mustang Convertible 2D
for only $5,821! I thought that was a pretty decent deal...
However, if it's your first car, you should probably go with something with a little better fuel economy so you can drive around more... Maybe like a Camry or something?