While it's not a book wholly dedicated to paper piecing, I learned a lot from the 6 pages of paper piecing instructions in the
Blocks to Diamonds book. The author shows a technique of using freezer paper and folding it back and then sewing right next to the fold (rather than sewing through the paper), so there's no paper to remove at the end. I've tried it and really like it. She also has good advice on how to use strips of fabric when piecing many of the skinny triangles her patterns have, and her way greatly reduces fabric waste that some other methods have. I have not read Carol Doak's book, so I can't compare the two. There are used copies of the book (available through Amazon and other outlets), so you can get the book at quite a moderate cost.