Continuing the blog chain begun by Kat, I'm listing here some books that shaped me when I was young.
Fantasy was huge. Huge. The two usual culprits, Tolkien and Lewis, made a tremendous impact on me. The Chronicles of Narnia affected me more than The Lord of the Rings when I was about nine, mostly because I was too young to understand some of the deeper spiritual aspects of TLOTR.
A third fantasy series that fired my imagination was Susan Cooper's The Dark Is Rising sequence. The original novel version of The Dark Is Rising bears no relation whatsoever to the recent movie, which was an altered-beyond-recognition piece of Hollywood tripe.
During my years in England, I discovered Arthur Ransome's series about children who go on solo boating and camping adventures. Swallows and Amazons is one of the books. Ransome's work fosters an independent spirit and a love of nature.
Along similar lines is an obscure book authored by two children and titled The Far-Distant Oxus. Instead of boating and camping, the independent children in this story go on a pony-trekking/camping trip. This novel is an amazing achievement from such young authors: I remember it as a riveting book. I keep trying to buy a copy on ebay, but they always run close to one hundred dollars, and I haven't summoned the necessary extravagance yet.
Addendum: I'm so glad I blogged about this today! I just checked ebay again and found a copy of The Far-Distant Oxus for only about $30. Some books from childhood are very comforting to have on the shelves. I'm looking forward to reading it to my daughter.