Eighteen original stories (eleven by women) in a celebratory 50th anniversary anthology of Signet authors and the first hardcover in this publisher's history. Signet introduced William Faulkner, Erskine Caldwell, Norman Mailer, Ralph Ellison, Truman Capote, and others to their first publication in paperback. Among their top authors included here are Stephen King (``L.T.'s Theory of Pets,'' a fizzle about a meatpacker's vanished wife and the pet dog and cat they fought over); Joyce Carol Oates (``Color Blind,'' a fair but weakly plotted story about a 32-year-old white virgin's obsession with a handsome 28-year-old black bartender who's studying for a Ph.D. in economics and lives in the apartment above her); and E.L. Doctorow (``Untitled,'' a strong prose poem about Holocaust victims and their artifacts collected by the Nazis). Doctorow's takes the biggest bite and is the most writerly writing here, his bravura piece perhaps heralding some longer work in progress. Also on hand is Erica Jong with one essay and nine new poems (``Songs in the Key of I'') about poetry as the Life Force; the poems are lively, but only ``Creation Myth, with Figs'' is memorable. Lawrence Block's ``Headaches and Bad Dreams'' is a gripping little yarn about a low- paid psychic counselor who happens to help locate a murdered girl, becomes famous, and then must face the consequences. Ed McBain's insightful and intriguing ``Where or When'' tells of an ex- detective turned bank dick after his partner is killed and he himself is wounded when facing two hoods with AK-47s in a bank robbery. Some wavering, but Signet has a winner here overall.