Of course this is going to look pretty different than the originals and I am not arrogant enough to think my list is very important but here is, excluding history books what truly inspired my games
Note that I had the benefit of coming in when gaming was just taking off and fantasy started to blossom in its modern form. This gave me a much wider range to choose from than Gary and Dave and the originals would have had
Notice too, my "peak gaming" era for me was 1989-1991. I started well before this (with Holmes Blue Book) but those years were the ones where I gamed the most and gaming took off for me.
Lastly I have read of the things that inspired the earliest gamers (save The Broken Sword which I have not yet seen a copy of) but these are the most inspirational ones
So without further adieu My Appendix N
The Ace Conan series. Yes I know this contains more than a little pastiche material. Thats OK. Even diluted Howard's works contains enough vibrancy to feel real in ways that say Tolkien does not
The Hobbit and to a lesser degree, Lord of the Rings.
Brian Froud's Faeries – that book scared the heck out of me as a kid for various reason.
Brian Froud's Faeries movie
Legend
Labyrinth
The Conan Movie for pure visual appeal
Bestmaster 1 and 2, great fun and good inspiration. The Kaber or whatever it was called throwing Iron crossed with made its way into many a game as the Kel
Katherine Brigg's Encyclopedia of Fairies: Hobgoblins, Brownies, Bogies, & Other Supernatural Creatures
Edith Hamilton's Mythology especially the Norse bits
Smurfs (yes Smurfs) Gargamel and Azrael are very much archetypal mad wizard and familiar
John Norman's Gor. Once you delete the Fem-Sub BDSM its very fun Sword and Planet stuff with wonderful historical pastiche
Deed of Paksenarion by Elizabeth Moon – probably the best D&D Paladin yet
Three Hearts and Three Lions by Poul Anderson
Mercedes Lackey's Valdemar stuff
Fritz Leiber's Newhon stuff
Louis L'Amour's The Walking Drum and Haunted Mesa
Ken Follet Pillars of the Earth
The SCA who will get its own post
Paradoxes of Defense by George Silver, this is how real medieval fights went and once I saw this it made a HUGE difference in how I perceived this stuff worked
Pretty much every pirate and swashbuckling movie ever made …
Phantom of the Opera musical
Starcraft. Misunderstood lines from the Protoss made up entire cultures in my game world.
Original Star Tek in particular Friday's Child (the Cappelans and their weapon the kligat were a big inspiration for the Vara) and the ahn'woon from Amok Time
and last Santa Claus Is Comin' to Town for starting me on the road to fleshing things out.