3x Cisco Catalyst 3750G-48PS Port switch, a few GBICs if you want to play with the fiber connectivity. 3x Cisco 2901 Routers, insure you get at least the T1 modules and cables. Make sure you buy the gear with mounting kits so you can rack them, along with purchasing the proper cables. If you want to learn more about VOIP you would need to purchase Cisco CUCM or something similar to Asterisk and possibly the processing modules for the switch/router or buy a switch that already has it licensed.

You may also want to get a rack to rack all the equipment as it can get pretty heavy and looks nice and professional when racked. The benefit of getting the older gear is that you can do all this for a few hundred dollars. If you want to learn the new stuff later on it will cost more, but you will know all of the hands on stuff by then and can truly benefit from virtual labs (remotely connected to physical hardware console port).