Thanks to everyone for their advice. It definitely makes sense to have an existing database of distances (or latitudes and longitudes) and check it first, before venturing out onto the web.

Moklevat's suggestion of http://sourceforge.net/projects/zips/ gives me a pre-packaged CSV file, based on the 2000 US Census data, of zip codes + latitudes and longitudes. Assuming that the data is accurate enough (I'll use Google to do some comparisons), it's a good basis for my work (http://mvhub.com/).

FYI, the US Postal Service charges $50/state and $700/all ZIP codes for this data (TIGER/ZIP+4). The woman I spoke with said that the data was updated every two or three years, which isn't that much better than using the Census data.

As for Geo::Google, one of its developers, Michael Trowbridge, responded to my bug report within half an hour, offering a patch. Turns out that Google's responses switched from UTF-8 character encoding to ASCII.

--John

In reply to Re: ZIP code distances by jrmtreebeard
in thread ZIP code distances by jrmtreebeard

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