The FTC makes it easy to file a complaint if your identity has been stolen. You can either use their online complaint form or you can file the compalint by phone using the FTC's Identity Theft Hotline, toll-free: 1-877-ID-THEFT (438-4338); TTY: 1-866-653-4261. You can also submit your complaint in writing to the following address:
Identity Theft Clearinghouse
Federal Trade Commission
600 Pennsylvania Avenue
NW, Washington, DC 20580.