John Joseph Adams' reprint anthologies range from SF about interstellar federations to epic fantasy to zombie horrors, for several different publishers over the past decade. Adams also does anthologies of original stories (not included here) and a couple titles listed below are mixed of originals and reprints. The composite TOC below includes only the reprinted stories; complete TOCs are at the isfdb links.
Most-reprinted authors: Orson Scott Card and George R.R. Martin (7 each), Paolo Bacigalupi and Robert Silverberg (6 each), Neil Gaiman and Stephen King (5 each).
Wastelands: Stories of the Apocalypse, (Night Shade Books, 2008)
[isfdb]
The Living Dead, (Night Shade Books, 2008)
[isfdb]
The Alchemist
(Audible)
-- Epic: Legends of Fantasy
The People of Sand and Slag
(F&SF Feb 2004)
-- Wastelands: Stories of the Apocalypse
Pop Squad
(F&SF Oct/Nov 2006)
-- Brave New Worlds
Shooting the Apocalypse
(The End Is Nigh, 2014)
-- Loosed Upon the World: The Saga Anthology of Climate Fiction
The Tamarisk Hunter
(High Country News Jun 26 2006)
-- Loosed Upon the World: The Saga Anthology of Climate Fiction
-- Wastelands 2: More Stories of the Apocalypse