Relatively few fantasy authors, and definitely not the ones you mention ... it would however be worth tracking the SF and Fantasy Masterworks reprint series (and the similar ones from the likes of Gollancz). Other than that: Le Guin, Wolfe, maybe de Lint.
I'd be interested in tracking the game associated books for WoTC and for that matter White Wolf. But by and large I don't read them.
On SF (stares at shelves, and just picking ones I think are still alive) - Iain Banks, Ken Macleod, Jack McDevitt, Niven, Bear, Brin, Pohl, Williamson, Vance, Silverberg, Colin Greenland, Paul McAuley, Haldeman, Neal Stephenson, Cherryh, Aldiss, Kim Robinson, John Barnes, Dan Simmons, George Effinger, Bruce Sterling, Benford, Nancy Kress, Card, Wolfe, Ian Watson, Greg Egan, Stephen Baxter, Clarke, Alastair Reynolds. And so on.
And, while I'm staring at the shelf ... is William A Barton the same William Barton that used to write on Traveller for Space Gamer?