Comment John Brunner + Roger Zelazny (Score 1) 1244
Two books I've loved and re-read over and over;
"The Traveller in Black" by John Brunner
http://en.wikipedia.org/wiki/The_Traveller_in_Black/
and one mentioned by some other folks, "Jack of Shadows" by Roger Zelazny.
http://en.wikipedia.org/wiki/Jack_of_Shadows/