Books I found inspiring or simply enjoyable during my formative years:
Watership Down
An old but good one: As a primary source of inspiration for me, I've come to believe no one should go without reading Richard Adams' Watership Down. I have yet to read a novel with better character or suspense development. The audio recording is also enjoyable.
The Princess and the Goblins
Another old but good one: I own an aged copy of George Macdonald's The Princess and the Goblins that includes appealing illustrations. But the story itself is no less engaging. Written for children, Macdonald's ability to transport readers to other world places so effortlessly left me inspired from an early age.
The Witch of Blackbird Pond
More young reader material that left a distinct impression on me. The Witch of Blackbird Pond, by one of my favorite authors of all time, Elizabeth George Speare, takes place during a unique, rather volatile time in history, but told from the perspective of a young, independent-thinking girl makes it timeless.
The Bronze Bow
The Bronze Bow, in my opinion, is even better than The Witch of Blackbird Pond. It is another piece by Speare that leads readers into a historical setting through a slowly unfolding plot. With the hot-tempered emotions of her protagonist, it's hard to set the piece aside.