I know I'm quite late to this party, and two things are going on here to make me so. First, life continues to happen and there are a couple of books on this list which, though very influential, I had a hard time remembering titles and authors' names for. Second, though I have written about the shift away from literature our hobby has made, I had failed to realize how radical that shift was until recently. In other words, I thought the exercise was a bit of fun, but not really important.
I am trying to be an ambassador for old school gaming and am close to convincing a 3.5 group to give me a chance to run a game with them. However, I found myself at a loss when trying to describe some of the settings I have ready to play. Here are a few of the terms, titles and names that had absolutely no meaning to my audience: high fantasy, dark fantasy, Lovecraft, Moorcock, Elric, Vance, Dying Earth, and the Black Company. When these failed to evoke any meaning, all of the examples that they came up with to find some kind of footing were self-referential — RPG settings or games.
I should know better, but I was stunned. Thus, in order to rectify this reality I came face to face with, even in only a small and insignificant way, I give you my own personal (inexhaustive) Appendix N:
The Old Testament. This is just chuck full of great stuff, especially if you like clerics, as I do. Elijah vs. the priests of Baal is still one of my all-time favorite stories (1Kings 18:1-46).
Alexander, Lloyd, The Chronicals of Prydain. These were the first full blown fantasy books I ever read. The image of the Black Cauldron pouring out an army of undead Cauldron-Born is hard not to be inspired by.
Cook, Glen, The Black Company. This book contributed to my group's proclivity towards dark fantasy and the nigh-hopeless fight against overwhelming evil. It inspired inclusion of several mercenary companies in our campaigns, and at least one campaign centered on all characters being members of a mercenary company. It also taught us that character death could be cool and even seen as an opportunity.
Leiber, Fritz. I remember reading several stories of Grey Mouser and Fafhrd, wondering how this affected D&D. I then went on to play my first thief, to create campaigns centered on being in a city, and even named a character Mouse.
Lovecraft, H.P. Lovecraft's incredible images of the creeping alien evil always at the edge of your vision, always hungering for your entire being, and the utter madness of choosing to follow it into oblivion have inspired me for years.
Moorcock, Michael, Stormbringer, etc. I was never much of a fan, and only vaguely remember trying to read some of his stuff; however, my friends were huge fans and the worlds I adventured in as a player were heavily influenced by Moorcock.
Tolkien, JRR, The Hobbit. I have to admit that as much as I admire the other works of Tolkien, it took me 20+ years of struggling to actually get through the Lord of the Rings trilogy and I never intend to read them again. However, the Hobbit profoundly affected the way I imagined D&D. The quest to recover the lost treasure of a by-gone era, forests filled with giant spiders, and magic swords with names are still integral to my understanding of the game.
Vance, Jack, The Dying Earth. I was one of those players who always chaffed at the Vancian magic of D&D until I read this. In someways, I am more comfortable with the strange, alien and genre blending world Vance created than most of the other fantasy worlds in this list.
Watt-Evans, Lawrence, The Seven Altars of Dûsarra. This was my introduction to S&S and I found this far more inspiring and useful than the stuff my friends were reading at the time (i.e. The Lord of the Rings). The protagonist (Garth the Overman) is sent to steal several powerful magical artifacts from the altars of dark and evil gods. Magic is scary; magic items are mysterious, powerful and dangerous to use; and, for those of you who point to S&S as a reason to remove the cleric from D&D, is chuck full of examples of clerics. I also credit this book for my proclivity to consistently play half-orcs (the closest thing in D&D to an Overman) on the rare occasions that I play a non-human PC.
Willey, Elizabeth, The Well-Favored Gentleman. This lovely book (one of a handful that I have read multiple times) is not only an example of what high-level D&D ought to be about — ruling, maintaining and protecting your own realm that you and your party have created — but also joyously plays with genre blending and world building using a kind of sub-planar understanding of realms.