If you haven’t checked it out, there’s a new (to me) service called GeoURL which allows you to put GPS coordinate meta-tags on your webpage and it will tell you who your website neighbors are. I’ve had it on my sidebar for a little while though, but I’m never sure if anyone looks at that.
A neat trick for finding out your latitude and longitude if you don’t have a GPS is to map your address on Yahoo Maps and zoom in all the way. Then in the address bar you should see your exact coordinates, or at least as close as the mapping system has you. There, now you have no excuse not to go add yourself.