or try.....

American Airlines Inc-Passenger Reservations & INF
Fort Worth, TX 76039
(516) 433-7300

or....

American Airlines Inc - Passenger Reservations & Aadvantage Information
Euless, TX 76039
(817) 267-1151

.... and if none of those work...

American Airlines Inc - AMR Corporation Headquarters General & Executive Offices
4333 Amon Carter Boulevard, Fort Worth, TX 76155
(817) 963-1234

The first one looks the most likely ... it's the 800 number with a different area code.... and the '433' instead of '443'.....