Living in New York?

Hey,

Are there any people here that live in New York? I wonder how expensive life is there. Any ideas on appartment costs etc for a single person? Or avarage wage of a New Yorker or something?
I'd like to go live there for a year once i graduate but I hear it's quite expensive, so it's not decided yet. Getting a visa for a year wouldn't be a problem, but I wouldn't have a working permit, so how difficult would it be to get a job? (By then I should have my bachelor in computer science and I'm also considering an economics-related master).
I could try earning my money with freelance, but the whole point would be to go out there, meet people, improve my English.. and not sitting behind my computer and program all day.

So any advice, ideas, experiences you want to share?