Granted, the book is older now, but it is also free (in digital form) last I checked.
This is THE BEST book on creating PowerPoint shows I've read. It completely changed the way I think about making presentations (and I make a lot of them.)
The book is short, concise, and meaty. And if you are interested in improving how you use PowerPoint, this book will have a huge positive impact on you.
This was written in 2002. Whilst technology has improved and some of the specifics have changed, the enteral ideas and principles are probably more important now than ever. The most important tip is don't ever put more than 6 words on a slide.