You can call your county's tax collector directly to find out the process for buying tax liens. Some counties will also advertise the process on their website, as well as providing instructions for how to register as a bidder. When counties list auctions on their websites, they will also provide information about the properties up for auction, when they go to auction, and the minimum bid. This list can help you identify if there are any properties you are interested in based on their location, property type, size, and minimum bid.