>>>This looks like it might work for you:
>>>
>>>http://www.a1vbcode.com/snippet-3557.asp
>>>
>>>(You will need a database with the longitudes and latitudes)
>>
>>Thanks, I thought there was a formula to calculate from the postal codes directly without having the need to get the latitude and longitude. I'll see more about those options.
>
>
>There's also this http://geocoder.ibegin.com/downloads.php
>
>US zip codes with longitudes and latitudes

Cool link thank you!