Fawn Hall, who gained fame as ex-Marine Lt. Col. Oliver North's loyal secretary, is writing an autobiography at age 28 about growing up in a family of career civil servants, according to her agent. Hall's book will be published by Warner Books in late 1989, William Morris Agency executive Norman Brokaw said. Brokaw did not disclose the terms of the deal with the New York-based publisher. Hall made headlines with her testimony before a congressional hearing into the Iran-Contra scandal about how she shredded and altered documents about arms deals. She has been working on her autobiography at a Malibu beach house, Brokaw said.