There is no aggregated source of information that I know of that will tell you what the auction results were. You can call the banks that had properties going to foreclosure that day in order to find out which properties went back to the bank and are now REO's. There are many sources of information that will give you information about upcoming auctions and what bank is foreclosing - for example: The Washington Post, http://www.realtytrac.com, http://www.foreclosures.com.
For the second part of you question ...
I agree with Monika on this - it just depends on the bank. Some banks handle many REO properties and are equipped with an REO department that can get them on the market quickly. Others are not well prepared for REO's and it may be a longer turn around time.
Some banks have the list on their site, and you can register with them and get the results.
Just a tip, but if you can identify who the trustee was handling the auction, you may be able to pass on your information to the lender and get a head start.
Manager, Restoration Capital LLC