Most of the houses shwon on here that say auction are homes that may or may not actually go to auction. They are just pulling information from public records and the property may end up having the auction date postponed. If you are serious about buying a home the best thing you can do is find an agent that you like and trust and work with them.
Most Real Estate website show homes that are listed. This means that the seller has hired a real estate agent to list their home in the Multiple Listing Service (MLS). The Auction website, on the other hand, shows homes that are "scheduled" for public auction. I say scheduled because many of the sales are postponed on the day of the auction.