I am working on some social media campaigns and want to know if anyone out here has a good way to track shares? What I am doing is product promotion where someone must like to see the info, that sends them to our site. They enter the giveaway. I want to be able to track who they share it with of their friends so I can offer them a way of winning "as a group". ie "The winner and 1-3 of their friends win X". Thoughts plz.