Your question specifically mentioned "tax foreclosure" properties rather than "lender" foreclosures. In March of 2009, properties revert to the county if past due 2006 county taxes are not paid by the owner. (Double check my "2006" statement. It might actually be "2007" taxes.) The county auctions those properties in September of 2009. Some counties in Michigan have excellent discussions of this process on their government websites. Wayne County just published in the Detroit Newspapers a huge list of all its properties that are on this list. Many of those properties, however, will be redeemed by their owners and will, therefore, never go to auction.