Who can I contact to file a complaint about my bank?

Q: Because of its slovenly customer service, I want to file a written complaint against Countrywide Bank, with which I have five CDs. Can you possibly provide me with the name and address of the federal agency responsible for handling complaints against banks?

A: I can tell you where to look. The regulator varies from one bank to the next. To find out the appropriate regulator for your bank, search here. Enter the name of the bank (leave off the state if you aren't sure.) In Countrywide's case, the site tells you that the regulator is the Office of Thrift Supervision. The Web site includes information about filing complaints.