Forum Moderators: phranque
www.arin.net - us
www.ripe.net - european
www.apnic.net - asia & pacific
Those are the main ones I find myself using although there may be a few others. If in doubt about where an IP is generally start with ARIN because if they aren't the right people they give you a hint who you need to try...
- Tony
Welcome to the board!
I use to run Analog on the raw logfiles. This freeware is available for most platforms and gives the contry of 95 % of visitors. It can do a lot more than that.
If you want to know about individual IP, Dreamquick is right. A lot of free whois lookup utilities are available online. I use Sam Spade on the Windows platform. This program can do too a lot more than that.