Anyone Got A List of Free Business Listing Domains?

Hello everyone, I'm an SEO Specialist of a company that handles the websites of many clients, and they're all local small businesses. I have little to no experience in link building, but my idea is just to get these websites in local business listing domains and local citations to get their DR up. Does anyone here have an excel sheet or database that has a list of all free business listing domains complete with DRs and whatnot? Ideally if they're organized by US state? Will sincerely appreciate all the help I can get. Thank you!