Joss Whedon books in order
12 books in the catalogue, about 65 hours of reading in all; the shortest takes 3 hours and the longest 16 hours.
12 standalone books in the catalogue.
Standalone books
The Harvest 3.1 h 
Buffy the Vampire Slayer (3 editions) 3.5 h 
Halloween Havoc 3.3 h 
Harvest Moon 2.9 h 
Obsidian Fate 5.4 h 
Shamrock Shenanigans 2.9 h 
Tales of the Slayer, Vol. II 4.9 h 
Dark Vengeance 3.7 h 
Chosen 12.6 h 
Astonishing X-Men 2.6 h 
Mystic Knoll 4.0 h 
Buffy the Vampire Slayer, Vol. 3 15.6 h