Looking up an IP address

I have a program for AOL instant messenger that allows me to see the IP address of any individual that looks at my away message. Well there is an individual that I do not have on my list that has been looking at my away message and i’ve been trying to figure out who it is. The program tells me the IP is aaa.bb.cc.xxx, whereas it gives me all the numbers except the last 3.

The program has a feature to lookup the name of the host, however it says the host name cannot be found. I also tried searching this address through multiple DNS lookups on the internet, but all of them come back as not available. Does anyone know an effective way of determining who the host of this IP address is?

www.arin.net can tell you.

Perfect, that worked. Thanks Joey G