Once the bank retakes the property, it becomes an REO so the control essentially shifts from the home owner to the lender.
Definitely get pre-approved prior to looking at homes. You must be ready to act quickly when you find a good foreclosure. Chances are other buyers will be competing for the same property. Any local bank should be able to assist you with the loan on a foreclosure.
Be sure to save a cushion in your finances. Typically in foreclosures there is cosmetic work that needs to be done and appliances are rarely in the home. Not all foreclosures are in bad condition, however you will find that a good majority need work.
Best of luck with your search,