Look for startup incubators and the companies in their portfolios. Reach out to the founders of those startups (the ones that look most viable), and contact them to do informational interviews about how they did it. They may be flattered that you are soliciting their advice and become willing to introduce you to their network of other entrepreneurs and influencers to strengthen your own network. Just be willing to offer some value up front to help them out with what they are working on, too, not just doing it for your own sake.