Some merchants choose to handle its own affiliate sales and payments. For example, the Elegant themes affiliate program is run from their website. If you see a product that others are selling then the first place to visit is the merchants website.
I'm going to give you my secret blueprint to earning big cash from Clickbank. Now, first of all, I am not going to teach you how to get your affiliate link, how to get setup, and how to join the Clickbank site.