Browse the MYSTERY eBook and Audiobook collection.
Search for MYSTERY FICTION in the Suffolk County catalog.
The Novelist Plus database has several dozen Recommended Reads lists for mysteries of all types. Find them by going into Novelist Plus and clicking on Recommended Reads and then Mysteries. Try Cooking Up Crime, Getting Cozy, and Police Procedurals for some examples.
This site will let you know if your favorite mystery author has a new book coming out: