Ideally governments would provide an index of registered businesses with some basic filtering (e.g. location or category of services provided) with a name, address, phone number, and url. Present in random order to be fair.

My state seems to have a search tool, but no list. It also only has name/address (so presumably it's more for serving legal papers or whatever).

If I want to find a plumber, I should be able to ask my government for a list of the licensed plumbers in my area.