I'm upgrading my rack to begin studying for another CCIE lab attempt. I have a bunch of slightly outdated gear that'd still be useful for a CCNA/CCNP candidate.
Routers:
2x 2501 (full memory/flash, all accessories) for $20 ea.
6x 3640 routers with full memory/flash and various interfaces
Switches:
2x 3550-24PWR-SMI $175/ea
I'd let the 3640 bare chassis go for $10. If you want memory, network modules, T1 WICs, etc then they'd be $40-50 ea.
These prices are less than Ebay -- shipping is a hassle.