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[benbakelaar]

"Hi
all, glad to be back, hope I have time to stick around and stay
involved. I'm currently in the middle of two web mapping projects, and
very briefly, I need an accurate database of all zip codes (hopefully
postal, but ZTCAs will be fine also) and their latitude and longitude
coordinates. If you search very hard (or with the right keyword) you
will find several free databases. I have one, with about 42741 records.
It's probably from around year 2000.

Apparently, it's not that
accurate. On Google Maps, ""from:27604 to:27587"" shows as 11.8 miles,
but using my script which references the zip code table and uses a
""great circle"" radius function to calculate distance, I get less than 5
miles when calculating distance between those two zips. Maybe this is a
problem between ZTCAs and postal zip codes.

Any explanations?
Any free sources out there? At this point, I'm even considering a paid
source. Any suggestions? Positive experiences with a certain company?

Thanks all,
Ben Bakelaar "