There are hundreds of novels based on the role playing game Dungeons and Dragons. At first D&D was published by TSR, they got bought out by Wizards of the Coast in 1997. Novels are generally based in campaign settings of the D&D universe. However the novels are open to general audiences (you don't have to play the game to understand the novels.) The best selling settings are Dragonlance and Forgotten Realms, the other settins are: Birthright, Dark Sun, Eberron, Greyhawk, Kara-Tur, Mystara, Planescape, Ravenloft, and Spelljammer.
Dungeons and Dragons: Birthright novels
Dungeons and Dragons: Dark Sun novels
Dungeons and Dragons: Dragonlance novels
Dungeons and Dragons: Eberron Novels
Dungeons and Dragons: Forgotten Realms novels
Dungeons and Dragons: Greyhawk novels
Dungeons and Dragons: Iconic Characters novels
Dungeons and Dragons: Mystara novels
Dungeons and Dragons: Planescape novels
Dungeons and Dragons: Ravenloft Novels
Dungeons and Dragons: Spelljammer Novels
Dungeons and Dragons: Comics and Graphic Novels
The Verdant Passage - or buy at BN
The Crimson Legion - or buy at BN
The Amber Enchantress - or buy at BN
The Obsidian Oracle - or buy at BN
The Cerulean Storm - or buy at BN
Tribe of One by Simon Hawke
The Outcast - or buy at BN
The Seeker - or buy at BN
The Nomad - or buy at BN
Chronicles of Athas - Various Authors
The Brazen Gambit - or buy at BN
The Darkness Before the Dawn - or buy at BN
The Broken Blade - or buy at BN
Cinnabar Shadows - or buy at BN
The Rise & Fall of a Dragon King - or buy at BN
Books not under a series by Various Authors
City Under the Sand, by Jeff Mariotte - or buy at BN
Under the Crimson Sun, by Keith R.A. DeCandido - or buy at BN
Death Mark, by Robert J. Schwalb - or buy at BN