Other favorite authors:
Isaac Asimov
Robert Heinlein
Thomas Pynchon (warning:
Gravity's Rainbow is a lot of work -- tread carefully)
Tom Robbins
Salman Rushdie (anything except "Fury" -- that was disappointing)
Mark Twain (natch

)
Charles Dickens (a couple of clinkers, but hey ... )
Kurt Vonnegut (especially earlier stuff)
James Michener (kind of invented a particular brand of historical fiction)
Bruce Sterling
Harlan Ellison (prefer his non-fiction, but the fiction is better than just fine)