Replying to Computer Geeks needed

Anyone know how to set up a trace route or how to find out someones info when all that is known is an AIM screenname?

I'm trying to find at least an IP address where its originating from, but if I could find out more (like real name address, etc) that would be huge. BTW, this is for a coworker who's 12 year old daughter has gotten involved with a predator online and the police are also already involved as well.

life is too short to have any regrets