I was trying to figure out how I can use Steve Blank's ideas on customer development. But my biggest issue was finding potential customers to interview. This post helps a lot.
i feel pretty strongly that making an explicit hypothesis about who the customer is (it's okay to be wrong!) completely solves this problem, because if you know who you are trying to reach, it's obvious. if you say: "im making scheduling software for film festivals" it's trivial to find an email or phone number and call them up and find out if you correct. if it's a consumer niche, find a forum or a blog and email someone.
Thanks.