What Sort Of Steamer Should I Buy?

I am a college student looking to furnish his first apartment & kitchen. I already have a basic set of pots and pans, a 12″ wok and all the cutlery imaginable. I really am looking for a steamer that I could use to steam vegetables. I just want something that comes with its own pot/pan or that i can stick over one of my other pots/wok.
Any help is appreciated!