I'm in the process of brainstorming on a writing topic that would involve interviewing people, taking their stories, changing the names and a few of the details, and creating a book from them. Do I need to have the people I am interviewing sign a release form?
I don't think so...I actually participated in something similar about ten years ago, regarding 'Regrets'. It was an online question/response, and each participant had the option of choosing to remain completely anonymous or whether or not to use their real name. The author sent me an email notification when the book was published, but I chose not to check into it.
I wrote a hub on someone and I changed names and facts and nothing has happened to me. Now I don't know the legalities in matters like that. I would check out some resources online to see if you can find out more. There are some online legal sites that can help you.