Hi,
I actually implemented something in PHP/mySQL that is a DB of latitudes
& longitudes and zipcodes. The formula computes distance 'as the crow
flies' using the radius of the Earth between 2 zipcodes, etc. It's
here:
http://www.deschuteshay.com/distance/ziptest1.php
I wish I could remember where I got this data... maybe
hotscripts.com?
If needed, I can gzip a mysql dump... I'll leave the PG conversion to
you :-) Very simple though... only 3 fields!
Tell me if you'd like... maybe I'll post a download link to a page.
