Josh Lanyon's Adrien English Mysteries, I Spy collection, Holmes and Moriarity set... Really anything by Josh.
Also I enjoy James Lear The Mitch Mitchell series, Vampire Vow and Thrall, and this one is a graphic novel but I love Artifice by Alex Woolfson
Other books I enjoy are the Sherlock Holmes ones, Richard Castle, James Patterson, Cassandra Clare and really anything in Thriller / horror / crime.