(http://foia.fbi.gov/privacy_instruc.pdf). Read instructions and Click Privacy act request form. ( http://foia.fbi.gov/privacy_request.pdf ). Fill this form, sign it and mail it (DO NOT FAX IT, FBI needs a signed original copy). Also include other information like previous addresses etc in a separate sheet.
Mail it to:
David M. Hardy
Section Chief
Records/Information Dissemination Section
Records Management Division, FBI
Washington, D.C. 20535