TITTERS 101: AN INTRODUCTION TO WOMEN'S LITERATURE by Anne Beatts, Judith Jacklin and Deanne Stillman (Perigee: $8.95). Here is a bogus college textbook, a tongue-in-cheek collection of "obscure" writings by women throughout history that parallel and parody actual works. Apparently, women writers have always been, and continue to be, chiefly concerned with sex, food, fashion and money, which bears out the historical view of many men. The authors--two of whom have worked on the National Lampoon--invoke the humorist's traditional license to satirize the oppressed group to which he or she belongs. But this ain't Richard Pryor or Woody Allen; no point is made, no commonality established. And it isn't funny. The material isn't sharp, fresh or intelligent enough, except for a distaff version of the "Canterbury Tales" and a send-up of an adolescent Anais Nin in love with her horse. Women readers beware: It's not an elbow in the ribs you'll be getting, but a pie in the face.