NEW YORK -- Tina Fey, already the busiest of stars thanks to her Emmy-winning role in "30 Rock" and definitive impersonation of Republican vice-presidential candidate Sarah Palin, is working on a book.

According to two publishing officials with knowledge of the negotiations, Little, Brown and Co. will release a book of humorous essays by the 38-year-old Fey. Her many writing credits include "30 Rock" and "Saturday Night Live," and the feature film "Mean Girls."