EMPIRE by Gore Vidal (Ballantine Books: $4.95). This latest in a series of historical novels on the American presidency takes place during the McKinley-Roosevelt Gilded Age.
TOOL OF THE TRADE by Joe Haldeman (Avon Books: $3.95). A professor and inventor of a mind-controlling device is in turn controlled by the KGB.
BRUISED FRUIT by Amy Ephron (St. Martin's: $3.50). Malibu model/actress is suspected of murdering her live-in lover.
THE UNLOVED by John Saul (Bantam Books: $4.50). Helena Devereux, matriarch of a South Carolina mansion, terrorizes her estranged son and maiden daughter in life--and after her death.
HEIRESS by Janet Dailey (Fawcett Gold Medal: $4.95). Two sisters first meet at their father's funeral, and neither has any intention of sharing the vast fortune he left.
SMALL SACRIFICES: A True Story of Passion and Murder by Ann Rule (Signet: $4.95). A mother shoots her three small children in hope of winning back the affection of her lover.
STRAIGHT ON TILL MORNING: The Biography of Beryl Markham by Mary S. Lovell (St. Martin's Press: $9.95). Markham, in the vanguard of women aviators, was one of the first to fly solo from England to North America.
MORE OF THE STRAIGHT DOPE by Cecil Adams (Ballantine Books: $8.95). Why are there 10 hot dogs to a pack and only eight buns? Inquiring minds have asked and received the answer to this and other mind-boggling questions in Adam's newspaper columns, compiled here.
THE HEALING BRAIN: Breakthrough Medical Discoveries About How the Brain Keeps Us Healthy by Robert Ornstein and David Sobel (Touchstone: $8.85). A fundamental task of the brain to maintain good health is examined by a noted neurologist collaborating with a physician who emphases holistic medicine.
CONVERSATIONS WITH CAPOTE by Lawrence Grobel (Signet: $3.95). Capote and Grobel's talks took place over a two- year period that included Capote' last interview.
SELF HELP / REFERENCE
THE ARMCHAIR MECHANIC: A Non-Mechanic's Guide to Understanding Your Car and Getting Good Repairs by Jack Gillis and Tom Kelly (Perennial Library: $8.95). Do you often feel that you and your mechanic are speaking in two different languages? Gillis and Kelly translate.
AFOOT AND AFIELD IN ORANGE COUNTY by Jerry Schad (Wilderness Press: $9.95). Orange County's little- known, but plentiful, hiking areas are mapped out and explored.