There are two sites I know of that sell used quilting frames and machines. You never know what you will find on there. ALOT of them are pricey, but then one will come along that is not. Keep looking! Do you have a Craigslist in your area? I just saw a couple local to me on there.
www.houseofhanson.com
ww.longarmuniversity.com
I know APQS has used machine on their home site under Forums. ALot are APQS brands, but they have other brands there too...good luck!