This post was inspired by Question #39 from this list.
I am a huge fan of Terry Pratchett’s books about Tiffany Aching. I listened to The Wee Free Men on audio-book over fifteen years ago. The thing I love about these books is that it actually downplays magic as part of what witches do and explores what it means to be a witch in terms of mindset as well as other ideas, such as the importance and power of stories.
In the realm of non-fiction, I would say that my favorite book is just about anything written by Diana Paxson, who I suspect might not refer to herself as a witch. But whether you’re talking about her tome on runes or her guide to deity possession, she offers a lot of helpful information for many witches (though I admit atheist witches may find her less helpful) can access easily. Paxson tends to be well-researched, has personal experience to offer, and writes in a style that is easy to follow.