when you say public posting, do you mean the MLS or the actual posting?
In Texas, whenever a bank forecloses, they have to post a notice at the county courthouse prior to the foreclosure sale. This is the first time anyone without insider info at the bank is going to know anythign about it. The sale is usually on the first or second Tuesday of each month. There will be an auction at the courthouse that day. If you want to learn how foreclosures work, I would suggest going to a foreclosure sale and watching.
The average real estate agent isnt going to know much more than you until it hits the MLS.