You'd be surprised how helpful people will be if they don't think you're trying to sell them. Make a list of 10-20 companies that might possibly be users, searc

You'd be surprised how helpful people will be if they don't think you're trying to sell them. Make a list of 10-20 companies that might possibly be users, search for their developers (search Google, look for a blog, look for a Twitter account, search LinkedIn), and get in touch with them. Say something like "Hi [name]. I see you're a developer at [company]. I'm building a service for people working with GIS data, and I'm trying to learn more about the space. Could I pick your brain over phone/Skype [or coffee/beer if they're local]?" You won't get a 100% success rate, but you'll learn a lot from the people who are willing to talk to you.