Did they keep your last month's rent or your security deposit? There is a difference. Are you still in the home? If you qualify, you may be able to find help at Legal Aid. They have a walk in legal self help clinic at the Cook Courthouse law library. Hope this helps.
I am sorry to hear about your situation. It is happening more and more frequently these days to good tenants who pay their rent on time each month. Unfortunately, it has been my experience that when the bank takes over through a foreclosure the tenant does not get their security deposit back. The security deposit is part of a contract between you and the former owner. You can probably sue the former landlord in small claims court for your security deposit, if it is not refunded and you left the home in good shape (take pictures before you move out since you don't know what will happen to the property after you vacate). The problem is, even though the landlord may owe you the money, he is not paying his other bills (like the mortgage) so you may also have difficulty collecting from him. You should check with a tenant/landlord attorney about your rights and then follow through.
Real Estate Consultant
RE/MAX Palos Verdes Realty