I had to think about this more than I expected.
When I was young, I read the Dragonlance books -without knowing they were D&D. So, they would have been early influences on me (along with The Hobbit and The Chronicles of Narnia). However, Dragonlance is D&D, so that don't count.
I also grew up within reasonable driving distance of where Frank Frazetta was located, but his influence on me would have come later.
I wanted to post something from Riddlemaster of Hed or the Lonewolf series. But, ultimately, I think one of the biggest early influences on me was this:
Ghosts & Goblins
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