1. A method comprising: performing a hidden web data extraction based on one or more of the following: product manufacturer, product dealer, and product seller; and based on the results of the hidden web data extraction, applying one or more tags to an entry in a business listing database, wherein the one or more tags describe (1) products for sale, or (2) services performed, by a business having an entry in the business listing database, wherein the method is performed by one or more special-purpose computing devices.