As you are asking this question from the "foreclosure in Martinez" category, it would appear you are asking about Trustee Auctions. These happen daily (sometime multiple times per day) on the courthouse steps at the local county courthouse. The properties that are scheduled to go to auction are public record. You can either go to the county to get this information, request it from your local title company or pay a service (such as ReTran.net or ForeclosureRadar.com or RealtyTrac.com) which will give you search and print features.
Now a word of caution. Trustee Auctions are not for the novice or single home homebuyer. The people who buy on the courthouse steps do this for a living. They know the business and they take some risks. Also, you MUST pay with cash (usually in the form of cashier's checks payable to yourself, which you endorse over to the lender/trustee when you win the bid) on the courthouse steps.
Also, when you look at Trulia and see properties going to auction for $20,000 and $30,000 this can be very misleading. Trulia gets it's foreclosure information from RealtyTrac, which is nothing more than an aggregator of information from the public records. The amount they show as the "price" if often just the amount the owner is delinquent on their loan, not the full amount of the loan. They also do not tell you about other liens. Perhaps this is a 2nd or 3rd trust deed. At the auction, you would have to take the property SUBJECT TO all senior liens. You often do not have an opportunity to see the interior of the property, so you don't know if they have stripped out the kitchen, bath, electrical wires, etc. If the house looks like a good deal, the professional auction buyers will most likely shut you out. Your best bet is to purchase this property once it has reverted back to the bank, or been purchased by an investor and rehabbed.
Hope this helps to clarify the process. If you want to discuss it further, please feel free to contact me. Dare to Dream.
Shel-lee Davis, CDPE, SFR, QSC
Your Real Estate Consultant for Life
RE/MAX Palos Verdes Realty