I will mention just a few authors i like and read/will read often in other genres.
Hardboiled crime fiction : Westlake/Richard Stark,Jim Thompson,Ross MacDonald,Raymond Chandler,Elmore Leonard,Ken Bruen,George Pelecanos,Dennis Lehane.
Other Crime : Michael Connolly,Arthur Conan Doyle.
Historical Fiction : C.S Forester,Conn Iggulden,Simon Scarrow,Jan Guillou.
Horror : Edgar Allan Poe,Richard Matheson,Stephen King.
Thriller: Frederick Forsyth,Ian Fleming,Barry Eisler,Mario Puzo,Robert Ludlum
Classic lit : Alexandre Dumas,Charles Dickens.
I do read the so called mainstream lit at times but not enough.
When its about non-fiction i read historical bios,social commentary books like John Dickie's Cosa Nostra. A scary book in that how horrible,powerful they are in real life. Much more dangerous than the romantic views of hollywood.