If you put it into google, you can occasionally find out more info about somebody - a phone number (with which you can find an address), etc. - although many times all you'll be getting is ISP info.
Sorry to hear about it man - don't do anything illegal.
Less pr0n bro. I've never once been hacked, never once had any identity theft issues or viruses of any sort. Take care with what you do with your computer and you won't have this problem.
There isn't much you can do ecause people are usually t[oo] smar[t] to really trace. Nev[er] use any illegal methods because you wouldn't want it to reflect back on yourself in a legal way.