I'm writing a book to help answer these questions. It's coming out on Manning Publications and you can pre-order it starting today.
https://www.manning.com/books/OAuth-2-in-Action
You can download the first chapter completely for free right now from the page above. With the pre-order, you'll get the first three chapters today as well as new chapters as they become available, including all updates as we refine the book. All the example source code is going up in GitHub:
https://github.com/oauthinaction
Plus, for a couple days, you can use the code mloauth2 to get 50% off the retail price.
We hope that people find this book informative, useful, and entertaining. If nothing else, our cover features a pretty epic mustache, which is hard to argue with.
- Justin