Grimes, Martha. The Old Contemptibles (New York: Little Brown, 1991) 333 p.

There are no real librarians here, but Melrose Plant impersonates one to get a job cataloging a manorial library. His real purpose is to gather information. He walks around with index cards, making notes while people think he is indexing. No one knows or cares anything about libraries, so his is an easy job.