A sampling of my finds from our yearly trek to the VNSA Used Book Sale:
Red Mars by Kim Stanley Robinson -- a modern classic sci-fi author that I have never gotten around to and what is considered his best book
Sci-Fi
Cyteen and Downbelow Station by C.J. Cherryh -- another "classic" modern author that I have not read before
Anvil of Stars by Greg Bear -- a sequel to Forge of God, which I've already read and liked
Fleet of Worlds by Larry Niven and Edward M. Lerner
Earthclan: Startide Rising & The Uplift War by David Brin -- I have read other Brin stuff and liked it.
Science Fiction: The Illustrated Encyclopedia by John Clute --This is a really nice coffee-table book with a fairly comprehensive overview of all science fiction (movies, TV, books, comics, etc.)
When looking for new sci-fi books, I let my own experience guide me but I also referred to several lists of the the top science fiction books of all time, including:
David Pringle's Science Fiction: The 100 Best Novels
Sci-Fi Lists: Top 100 Sci-Fi Books
NPR's Top 100 Science Fiction and Fantasy Novels
Science Non-Fiction
Chaos: Making a New Science by James Gleick
Quantum Man: Richard Feynman's Life in Science by Lawrence M. Krauss -- Feynman and Krauss ... two of my scientific heroes.
Not a Drop to Drink: America's Water Crisis by Ken Midkiff
General Non-Fiction & Philosophy
Don't Eat This Book: Fast Food and the Supersizing of America by Morgan Spurlock -- a companion piece to the excellent documentary Super Size Me
The Island at the Center of the World: The Epic Story of Dutch Manhattan and the Forgotten Colony that Shaped America by Russell Shorto
Letters to a Young Teacher by Jonathan Kozol
Towards a New Architecture by Le Corbusier -- I'm a modernist nerd and this is considered one of the "bibles" of modernism.
Postcards from Ed (Abbey): Dispatches and Salvos from an American Iconoclast
Bertrand Russell: A Collection of Critical Essays edited by D.F. Pears
"For me science fiction is a way of thinking, a way of logic that bypasses a lot of nonsense. It allows people to look directly at important subjects." -- Gene Roddenberry