Melisa C. Michaels. Sister to the Rain (1998) 320 pp. [pbo]
Publishers description: The last time P.I. Rosie Lavine got involved with elves, she almost didnt survive. This time the case seems much simpler: investigate strange noises and petty disturbances occurring at a secluded mixed-race artists colony in the California hills. For Rose and her partner, Shannon, uncovering the identity of the Trouble is a priority—until a human is killed and the stakes are suddenly raised. Now they must uncover the secrets of this seemingly peaceful enclave. Secrets that could land them right in the middle of an elven revolution!
Setting: San Francisco