THE PLAYWRIGHT'S HANDBOOK by Frank Pike and Thomas G. Dunn (New American Library: $8.95). Like Syd Field's two popular books on screen writing, "Screenplay" and "The Foundations of Screenwriting," this text should be paid attention to by aspiring playwrights and teachers in the field of theater alike. The authors base their work on the belief that contemporary playwrights should collaborate in workshops with other theater people--the actors, directors, even the set designers! (Perhaps this isn't quite a revolutionary idea; Shakespeare was rumored to have been an actor and active in traveling theater groups in addition to his career as a writer.) By doing so, they claim, the playwright is able to get invaluable feedback on what he/she has written as well as an insight into the sometimes ugly reality of soaring production costs. This workshop approach was developed in the 1960s by small, experimental theater groups in New York and elsewhere in the country, but only recently has come to dominate the American theater scene from regional colleges to Broadway. The authors cover everything from simply finding the right workshop to join to the complex mechanics involved in play writing.