Janet Skarbek is 36 years old and lives in Cinnaminson, N.J. She is the author of ''Planning Your Future: A Guide for Professional Women,'' a book about managing the unknown. It was published in 2001 by the Professional Women's Institute, a small networking and support organization that Skarbek and three other women jointly ran out of their homes. ''Planning Your Future'' presents a world where exemplary order and control are possible. It urges working women to get ahead by thinking ahead: choosing a career with their children in mind, timing pregnancies so as not to lose traction at work. It...