On a Pale Horse: Incarnations of Immortality #1 (1991)

The Man Who Murdered Death! In a comtemporary society where magic and science are both taken for granted, a man named Zane, down on his luck, attempts suicide -- only to find himself confronting and killing the embodiment of Death! Zane is forced to take his place as one of the Incarnations of Immorality, along with Fate, Time, War, and Mother Nature. Book One: " To Buy a Stone"  begins a story of a beautiful women, adventures in Hell, and a Heaven as loaded with bureacracy as the next business!