PHP Filter non-usa Visitors

Anyone have a solution, preferably free, to be a开发者_运维问答ble to take anyone hitting the site from a non-usa IP address and send them to a page saying "For US visitors only"?

See this tutorial. You can filter non-US IPs with the codes in tutorial. It requires PHP and MySQL.

You need a database of IP addresses. http://www.maxmind.com/app/geoip_country Something like this should do it