Maybe you want to take a look at the following links: http://drupal.org/node/19983 http://www.darkshire.org/~jhkim/public_html/programming/zipcodes/ http://www.phplinkdirectory.com/forum/viewtopic.php?t=427&highlight=state+town Hope this helps
I'm yet to find a solution that comes with adequate datasets. You typically have to import your own. Keeping SEO in mind, the only way I've been able to do it is use something like the http://www.biz-directory.org/ script (the freebie only gives you one tier, unlike the paid one that gives you dual tiers, allowing cross referencing say, products against geo political regions or the like) - or of course the other way is to build it from the ground up, like http://www.reciprocal-links.info Remember too that you need to populate a directory like that with content, you'll end up with literally hundreds of thousands of pages - I prefer book editorials/reviews from Amazon myself (as you'll see in the reciprocal-links.info site - always relevant and of interest to your audience).. Cheers, JL