There are a ton of thrift stores in the OKC area. I would suggest the area from MacArthur and Reno to NW 50th and May. Really though you can break it out in to sections and spend all day and still not hit all of the the thrift stores. Its pretty crazy really. It is mostly junk but I have found some pretty amazing finds. The best was a pair of John Lobb Williams. Not my size though.