I only have 3 "near" me and even them its a bit of a chore to get to them. Ive checked a few tines but they don't have much of a used section. I usually just from regular stuff and beat to crap discs. Best Ive come up with so far is a pretty nice Rancho Roc and a really nice tie dyed Z buzzz that actually happened to me a misprint disc. Didn't know when I bought it, its stamped underneath. Couldn't tell you whats misprinted on it though looks fine to me and its in basically perfect shape. Neither is rare by any stretch but 2 really nice throwers and a decent price.
those are the highlights I suppose, I've also got a few cheap "range" discs from them too.