If traditional thrift shops are too pricey, I've gotten awesome things from Craig's List and Freecycle (freecycle.org)
Since it's getting to be the end of the college academic year, college kids are getting rid of all sorts of stuff for insanely cheap prices. They're posting on Craig's List, fliers around the colleges.
If you work at university/college, you might be able to find some good stuff in the dorms by the garbage can. It always amazed me what people would throw out. Perfectly beautiful and usable lamps, chairs, furniture, etc.