Spenser is a wisecracking former boxer turned private investigator and he is just settling into his new office when enters Harv Shepard, a beleaguered businessman who is looking for someone to help locate his runaway wife. So begins Promised Land, the fourth novel by Robert Parker, that follows the exploits of his cerebral but tough character, detective Spenser. Why Harv Shepard's wife abandoned her family and exactly where she has gone comprise only half the intrigue in this story, though Spens