Redirect user based on proximity to a set of given cities?

[eluser]Kevin Smith[/eluser]
Does anyone know of a script or a method to redirect users to a particular URL based on their proximity to a given city? It doesn't have to be CI based or anything. I'm just trying to find this online and can't. Note: I'm a designer that dabbles with PHP and server admin. Not a genius here, but I'll probably know what you're talking about. Anyone know of any solutions here?

[eluser]elvix[/eluser]
seems like you're asking about IP to location services? There's a number of them out there, a google search will dig them up.

[eluser]Mike Ryan[/eluser]
elvix is correct, although a more specific search term might be IP geolocation.