This kind of market is usually called Multi-Sided Markets. It is hard to help without knowing more details about the product, but Harvard Business Review has a great article on it, which should help you with your issue: http://hbr.org/2006/10/strategies-for-two-sided-markets/ar/1

Here is another article that might be useful: http://www.strategy-business.com/article/03301?gko=16442