This is my collection of Zelazny.
Frost and Fire, The Changeling, Coils, Lord Demon, This Immortal, The Dream Master, Dilvish the Damned,
(The Amber Novels): Nine Princes in Amber, The Guns of Avalon, The Sign of the Unicorn, The Hand of Oberon, The Courts of Chaos, The Trumps of Doom, Blood of Amber, Sign of Chaos, Knight of Shadows, The Prince of Chaos
Bridge of Ashes, Creatures of Light and Darkness, Lord of Light, Damnation Alley, Eye of Cat, Isle of the Dead, Jack of Shadows, The Mask of Loki, Roadmarks, To Die in Italbar, Alien Speedway (Book 1), If at Faust you don't Succeed, Bring me the Head of Prince Charming, A night in Lonesome October (very Bradburylike), Doorways in the Sand (my personal favorite), A Farce to be Reckoned With, Donnerjack, Psychoshop, The Last Defender of Camelot, The Doors of His Face the Lamps of His Eyes, Unicorn Variations.
Some are short story collections, some were co-written with other great writers. I am sure that I have a couple loaned out that have not come back. I am also sure that there are more out there. (When I hit the book store, I start at "Z".) He also wrote for magazines and wrote articles on writing and science fiction. I found the book "Warriors of Blood and Dream", which he edited, just before his death. In the forward, he describes his Martial Arts journey, including information about his collegiate fencing. My son gave up Tae Kwan Do, and took up fencing. My daughter took up fencing, but really wants a broadsword. I was trying out Kendo, but have let it go for now to concentrate on the TKD, Hapkido, and the cane as a practical weapon.
I din't count them. But if you think that is a lot by one author, you should see my wife's collection of Andre Norton.