This contribution will populate state and city by zip and populate country by IP.
The customers can manually change the the information if needed still. I made this and you can test it at http:www.thewaytoherheart.com
In this version it uses a flat file of for the zip codes I will be adding this to the database as soon as I get some feedback and time.
Please BACKUP BACKUP BACKUP I am not responsible if this messes up your site!!!!

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