"The immortal Ray Bradbury, Eric Frank Russell, David Weber, David Drake, Frank Herbert, Keith Laumer, Robert Heinlein, the good Doctor Asimov, Murray Leinster, Anne McAffrey, Ursula K Leguin, MIchael Moorcock, Dean Koontz, Fred Pohl, Gordon Dickson, Larry Niven, James P Hogan,Lois Bujold, Jerry Pournelle, Andre Norton, John Ringo, Fred Saberhagen, Sir Arthur C. Clarke are a few that come to mind. My wife wants me to empty my library, as I have kept every book worth rereading since I was oh five. Yes, there is a copy of 'Have spacesuit will travel', as well as 1st revised edition Lord of the Rings trilogy..."
Edit to add: Jim Baen has a free library at his website, get David Weber's first two books about Honr Harrington" on Basilisk Station" and "Honor of the Queen" or maybe "A Short Victorius War"
www.baenbooks.com