After conducting more than 20,000 interviews in my career, I have a few tips I'd like to share. Funny how these tips also apply to everyday conversation.
1. Be warm and welcoming. Unless you really hate the artist's work, say something positive about the book, CD, whatever -- even the biggest stars like compliments. This is more than good manners -- it helps to relax the guest. A relaxed guest will be more forthcoming than a nervous, uptight guest who figures you're going ask about that DUI, the rehab or the lawsuit by the ex.
2. Think of it as a conversation and not an interview. If you do an interview, it will likely SOUND like an interview. How do you talk to a friend over a beer? First you LISTEN -- and you react to what you've heard. If someone tells me something really interesting, I'll simply say, "Really?" or "No!" Those are little words of encouragement that signal the speaker to continue -- and to expand on previous remarks. If your guest is truly confusing, try "Huh?" Works for me.
3. Try to have an arc to the interview -- a continuum that follows an orderly path through a life, a career, a project. Another option is to divide it into sections: Art, personal stuff, pet causes or community service. Make it easy for your listener to follow the story.
4. Don't trust the web. Errors last forever in cyberspace. (I love reading quotes attributed to me that I never said. Whoever wrote my Wikipedia entry got my date of birth wrong and said I home-schooled all my kids. At least I'm allowed to edit THAT one.) If something you find seems outrageous, it could be for a reason. Try saying, "It's not really true that you make stew from roadkill, right?"
5. Indulge yourself. Ask the question you've always wanted to ask. "What's that lyric about?" "What inspired that painting?" "That's such a sad song -- did your dog die on the day you wrote that?" But then you have to be prepared if the guest says, "Yes, he did, and I still miss him terribly."