Are there any non-fiction books written about sorcery?
Too many to list - major booksellers have departments filled with them (New Age, Occult, etc)
Let's work through this question one bit at a time.
First let's get a definition of what sorcery is - which is a type of magick (the added "k" on magick used by some to indicate "real" magick vs the slight of hand and card tricks you see on a stage or as part of a performance). Sorcery is the use of power utilizing spirits, often evil spirits, and often for the use of divination.
The next question to ask is - Is it possible for non-fiction books on this topic to exist? That is, does sorcery exist?
While the answer to this question will vary wildly depending on the answerer's belief systems, there is no doubt that some people do believe that sorcery exists and as such, there are books that talk about how to do sorcery and other types of magick.
Most large booksellers (in Canada, this would be Chapters, among others) have sections with a lot of titles available for sale. They are often next to the religious section and can often be found in sections such as New Age, Occult, and other related departments. And so yes, there are numerous titles out there concerning sorcery, witchcraft, shamanism, and other forms of the metaphysical.
And now for a bit of caution - as someone who reads Tarot, views himself as a shaman, performs protection and other spells, and the like, I would encourage you to do a couple of things - 1. to start small - my journey began with the study of Tarot and it is a good place to start understanding the nature of your relation to the unseen, and 2. to approach this study with humility and patience. It is said that when the student is ready, a teacher will come - trust in that.