Great question. I get this question all the time and the best place to start is to look at your own network.

Before reaching out cold which you will eventually have to do, ask family and friends who they know or you probably know of some personally. There are already people you know who are high level entrepreneurs that would be great.

yes the other ways are good also ie linkedin, twitter,etc

what format are you going to use to do the interview..audio, video, written or all?

I talk about this exact question here... http://www.inspiredinsider.com/top-3-faqs-about-interviewing-answered/

Let me know how I can help.