In my opinion the most important part of internet marketing is to define your target audience. Then use as much sources as you can to reach it! I'm prefer to start with social media, such as fb, twitter, and instagram.
Yes, this is a very powerful tool. Many people create target groups in social networks. And if you offer there sa product, then undoubtedly you will find many partners. But with each partner you need to have a personal conversation and explain why he should buy your product