What? Eight? There are only four Warcraft games. Though I see you are counting the four expansions as games. The story of how the Burning Legion came to Azeroth is briefly explained in the manual for Warcraft III, but there are several contradictions between that, and what is written in the books and what I've figured about World of Warcraft.

Perhaps a game off 1984?
I've not really bothered to think about the details, but maybe it could pass as a point and click game?
It seems to me that your typical novel seems best suited to the point and click genre, now that I think of it.
And just to throw my two cents in on this whole Star Wars, Lord of the Rings, move-to-games shenanigan:
Knights of the Old Republic is one of my favorite games and Rogue Squadron is fun. From what I remember of Pod Racer, it was fun, too. Haven't really played many other Star Wars games that are worth mentioning (never played several).
There are also some good games based off other franchises. But they seem to be diamonds in the rough. Mickey Mania, Duck Tales, GoldenEye. Heck Cool Spot was even fun and it was a 7-Up game.

OH!
I know a game I played that was based on a book, The Witcher EE.
Yes, quite good.