Does the bank have to give me details if they forclosed then auctioned my house,?

does the bank have to give me details if they forclosed then auctioned my house, i owed 57,000 its value was around 100,000 ,do they have to let me know how much they sold it for? and can they buy it themselves?? should i check if and wear it was auctioned?? help im lost i have three children, and i am disabled, the reason i lost the house is my ex husband owes 35,000 in child support arrears, there are warrents for his arrest but nothing seems to be getting done and now as a result me and my children will be on the street in a matter of weeks???