Can I determine is a surfer is in the US or Canada?

More specifically, a 100% reliable method?

[limitup]

Subject says it all. Can I reliably determine if a visitor to my site is in the US or Canada via their IP address? Is there a database of ip ranges, etc. somewhere I can get my hands on for this person? I've seen sites do this before so I'm assuming it can be done.

Basically I want to prevent anyone NOT in the US or Canada from signing up at my site. It's a free offer that I pay affiliates on, and it would be just one more layer in my anti-fraud systems.

[adb64]

Hi limitup,

You may want to try the free ip to country database that can be found at [ip-to-country.webhosting.info...] . But a 100% reliable method can never be reached. I think this database is about 95% correct, it works fine for me.