Pale Kings and Princes, by Robert B. Parker. New York: Delacorte Press. 256 pp. $15.95. Last year's Spenser novel, ``Taming a Sea-Horse,'' was a disappointment. Robert Parker makes up for it with ``Pale Kings and Princes,'' his 14th novel featuring the Boston-based, tough-guy private detective who quotes poetry and cooks gourmet meals for the woman he loves, psychotherapist Susan Silverman. When Spenser is hired by a newspaper to find the murderer of a reporter who was investigating the cocaine trade in Wheaton, Mass., he enlists the aid of Susan, his sidekick, Hawk, and a cooperative state trooper. This novel is a pleasure to read. The dialogue crackles, and both the suspense and Spenser's renewed relationship with Susan (an added dimension missing from the TV series this year) are strong.