i looked up the yellow pages for an ex-commercial equipment dealer. Should be one in your area.
That way you get quality stuff instead of the cheap shit that you get in many stores and you know that it will hold more weight than you could ever dream of squatting. You can also strike some pretty good deals as well.
karate kid I bought a bodysolid last summer and it is still holdin tight. You needn't worry. They've also got a lifetime warranty.
Might also try a local high school like somebody said. When they get new equipment in...they gotta shuffle and get rid of stuff sometimes to make room for the new goods. Might get one cheap that way.
I made my own. Cost: $40.00. some of the material I already have. Although I really dont use it that much since ive got a low back injury that will keep me from heavy squating for the rest of my life. Im a benchin fool though.