zombies, hmm . . . other than Laurell K. Hamilton's books, in which the main character is a zombie raiser, the only other ones I can think of are Piers Anthony's Xanth series, which feature zombies as characters, (although they aren't "zombie books" per se.)
Others which have not been mentioned are P.N. Elrods Vampire Files books, which feature a vamp P.I. and Charlaine Harris's Southern Vampire series, which are really fun and well written. They feature a girl who is a telepath who gets sucked into vampire and werepeople stuff.