One more thing - have you seen this video - https://www.chamberofcommerce.com/videos/top5reasonstojoinchamber. A couple of points:
(1) I honestly didn't hear a single thing that was worth spending money on. Let me know if you agree.
(2) At the very end, he does say that you can get your $179 refunded in the first 30 days and still remain on their site. So, that's a (backhanded) way to get listed for free. I still say it's not worth it.
So, emailed them to see where they get their data from and the said the following:
"We receive our information from several third party sources, but chamberofcommerce.com uses Acxiom as our primary data source."