Ask HN: How to effectively use Mechanical Turk for user interview?

I am developing a site that examines news and current events and trends through history. I developed a coming soon page (www.historybehindnews.com) and got some sign-ups from LinkedIn, Medium and YCSchool. It was cool. Now I want to hone in and see where people that would "love" this hangout.

I've thought of using Mechanical Turk for customer interviews. The trouble is that I am not sure people that are working on Mturk would actually be my customers? Any comments on this?

Also, if not MTurk, then what else is out there? Please note that I was thinking of doing phone interviews with MTurk - each interview 10 mins, and the task would be done in one day.