If you are into a trilogy I would recommend Kim Stanley Robinson's Mars Trilogy -Red Mars, Green Mars and Blue Mars. My favorite current authors are Dan Simmons - Hyperium series and, although I'm not into the Horror genre, Simmons writes some great ones. The Alternate History genre is placed within SF because the earlier stories all involved time travel but that is not a factor in many (and IMO the best). The masters of this genre are Harry Turtledove -The World War series and dozens more, the best starter is The Agent of Byzantium. Harry Harrison - the West of Eden trilogy and Stars and Stripes in Peril series.
For non-fiction a must read is Charles Mann's 1492, it's an incredible account of the pre - Columbian people and cultures of the Western Hemisphere
Cool! All of those sound pretty interesting, Jim. Thanks!
The only Harry Harrison I've read is the first Bill the Galactic Hero, which I remember being of the silly humor sort. Does that carry through to his other books?
No most of his works are serious SF - although he has written some funny stuff.
Good to know!
I'm reading Stephen King's new book 11/23/63 and it is so different from his other books. I love it! It is about 900 pages but it will keep you glued.
I'd recommend just about anything by Alastair Reynolds. If you like space opera then he's your guy. My personal favorite is 'Pushing Ice'.
Also Richard Morgan. The Altered Carbon series and 'Black Man' or 'Thirteen' as it's titled in some countries.
I'm currently reading Peter Hamilton but as yet can't make a recommendation.