I would imagine you would contact Immigration.

As far as I can tell, the form for which you are looking is FS-240 From the website of the US Department of State, http://travel.state.gov/passport/get/first/first_828.html "OBTAINING COPIES OF THE FS-240, DS-1350, AND PANAMA CANAL ZONE BIRTH CERTIFICATES The DS-1350 or a replacement FS-240 can be obtained by writing to: Vital Records Section Passport Services 1111 19th Street, NW, Suite 510 Washington, D.C. 20522-1705 A written request must be notarized and must include a copy of valid photo identification of the requester. The written request must include: (1) full name of child at birth (plus any adoptive names) (2) date and place of birth (3) names of parents (4) serial number, if known, of the FS-240 (on those issued after November 1, 1990) if known (5) any available passport information (6) signature of requester and (7) notarized affidavit for a replacement FS-240 (if applicable). Note: For Panama Canal Zone (PCZ) birth certificates, just include items (1) through (3). The fee for an FS-240 is $30. The fees for DS-1350 and PCZ certificates are $30 for the first copy, $20 each additional copy . Make check or bank draft drawn on a bank in the United States, or money order, payable to the "Department of State." The Department will assume no responsibility for cash lost in the mail. Documents will be provided to the person who is the subject of the Report of Birth, the subject’s parents, the subject’s legal guardian, authorized government agency, or a person who submits written authorization from the subject of the Report of Birth. CERTIFICATE OF CITIZENSHIP ISSUED BY THE IMMIGRATION AND NATURALIZATION SERVICE" For more information, the link, once again is http://travel.state.gov/passport/get/first/first_828.html