If you need a lot of books, I'd recommend the Bartimaeus Trilogy, the Artemis Fowl series, and the Discworld Series.
They have varying degrees of fantasy, Bartimaeus being the grittiest, followed by Artemis Fowl being more of a high-action thing than dark, and the Discworld series being brilliantly humorous and entertaining. Bartimaeus still employs a great deal of humor though, just in a much more cynical way.