Homes in foreclosure that make it to auction are typically auctioned by the sheriff's department of the county the property is located. If the property is already bank owned, properties are typically marketed by real estate agents. Some of these go to auction. To find out who the auctioneer is you would likely need to call a real estate agent. I see foreclosure in Wauwatosa, so it would likely be the milwaukee county sheriff's department. They have a website listing upcoming sales which are held every Tuesday. There are currently 381 on the list. Only a portion actually make it to sale with the majority purchased by the party foreclosing.