Interesting article on sourcing leads:
But for startups, early stage companies and small/medium businesses, uncovering qualified leads on a tight budget is a very different situation, and one that many organizations struggle to figure out. While I am not suggesting we have discovered the holy grail here at Work Market, I am going to share some of the more effective methods that we have used, and look forward to additional comments on what this readership finds successful.
From http://www.avc.com/a_vc/2013/06/mba-mondays-sales-leads-on-a-small-budget.html