I wish I knew of places to find stuff like that. Best I can ever find is curbside trash stuff and an occasional Freecycle find. When the CompUSA around here was clearing out their stuff, they didn't really have anything worth buying on markdown... and what Mac stuff they did have was barely discounted at all (even when the store was going to close within a week). Other than the set of headphones I needed, the best I ever found was an audio y-splitter and an ethernet dongle for a buck.

I've probably said this before, but if it was me there, I'd grab all the Apple poster ads I could get my hands on. Even if I didn't keep them, I'm sure someone would pay something for them on eBay and the like. The way I am, anything with an Apple logo on it would be fair game, working or not.