Athelstan is right...
Paul...Try this...
http://www.dnsstuff.com/ Once you find out who owns the IP address you can write to them asking for the telephone number if it is a dial up or the address if the IP is fixed.
You can also E-mail the ISP and get the IP address shut down.
If they have used something like ghost surf the IP address you received will have been bounced off anonymous servers from around the world. That makes the IP address fake. So then you wont be able to trace it...
LX
[Edited on 20-3-2004 by kwikbitch]