if you are relying on whois type websites to give you the location of his ip you might be surprised when you get there :p
usually the ips are regged in the general area, not every single users house.. think about it.. my ip comes up 5km away.. still close tho.
but yeah... it should be the general area.... but may not be....
You raise a very good point, but this is also dependant on the ISP.
For example, my ISP gives me a static BLOCK of IP's that are shared between each of the consumers on a given node, now virgin media have a node with 160meters of every house thye service, and my IP Address comes back to my node which is at the end of my road.
Tracing People via IP is not a simple method, but it will allow you to get very very very close without so much as breaking a sweat.......