detecting people i.p adresses....

A friend of mine got his computer hacked, they hacked into his youtube account and used his i.p adress to send out freind requests, would there be a way of tracking their i.p adress? or if someone has a wwebsite, is there a way to find out their i.p adress and physical adress?

Sounds like your buddy's computer is a newly minted member of some lovely botnet.

"or if someone has a wwebsite, is there a way to find out their i.p adress and physical adress?"
^ By this do you mean if you own a website that was hacked, can you find their IP? Well, look at the logs.

If you know of the hacker's website, check the IP of the site, look at whois, and talk to their host.

More info needed plz

Any half decent hacker would use multiple proxies.. and even if you had the IP the attack was carried out from and it was not a proxy (which is highly improbable) you would still have to convince the ISP and they probably won't give YOU the address, but at most alert authorities..

If your friend's computer was infected.. good luck

Sorry to say there's almost nothing you can do unless you're an expert. Even then, if they used any stealth techniques at all it's like finding a needle in a haystack.