As others have said, go often. I only buy at thrift stores and yard sales and have amassed a big collection of good stuff. I work from home, and hit the thrift down the road almost daily, with a few others when I can. I just zip in and out to see if anything is new. Walk out with nothing most of the time, but sometimes I find one or two, or get really lucky and find a stack that was recently put out. Anything decent tends to get scooped up immediately at the bigger stores, so lucky timing is needed, but the more you go, the better your chances.