If you are talking about the Trustee's Sale, I will advise you to be well informed about how they work. Two of the most important issues to consider is that they are "cash" purchases and you need to come up with the entirety of the purchase price within 24 hrs, or you will loose your deposit. The other issue is that it is truly an As-Is purchase. If find any issues after you purchased it you are out of luck. And for most buyers it is not feasible to pay for a professional inspection on every home they intend to bid - that is assuming that you can have access to the property, which many times you don't.
Also remember that the lienholders will not let them go too cheap. They do bid in their own properties, that is how they acquire them back to sell later as a foreclosed property.
Unless you have all the cash available and a high risk tolerance, a Trustee's Sale might not be a good option for you. Other type of auctions work differently and most times are no better.
The property itself should have a notice indicating when and where the trustee's sale will be. They are generally held in the court.
Good luck and please let me know if you will need further help.
ABR - Accredited Buyer Representative