The individual accounts are obtained through resellers, who should have their rates on their web sites. There are only eleven of them in the U.S. Click the "Reseller Locator" link to get the list.
The point about this being a freebie is well taken. We have a nearby small city called Stevenson, WA, that offers free Wi-Fi, you just have to start from a homepage that lists city businesses. A lot of folks would just drive on through, otherwise.