1. No, I didn't. Everyone was very gracious and there was never an expectation for money. For some people like patio11 and Jason Fried my book sales would not represent a meaningful amount of money. It's better to not even bring it up. Many of the people I interviewed have become friends and I try to help them in any way possible.

For companies I didn't contact them in most cases. The few I did talk to were thrilled their designs were being used as an example in a book.

2. This book is light on data and studies. That's a short coming. These are all techniques that I know work well, but I don't always have a study to back it up.

3. I'm not sure what you mean about a sample page for the case study. To better market it? That case study has a lot of great content and I'll be working with the company further to write a lot more articles and tutorials around what we all learned in that process.