Clickbank paid more money than any other affiliate network because it is the largest supplier of digital products. Clickbank paid more than 1.2$ Billion, that's right, 1200$ million dollars paid to affiliates like you.
But making money with Clickbank is not easy, who wants to purchase a digital product? In the US, a lot of people do and the secret is to learn how to make them buy from you.
1. Generate traffic, lots of traffic, without traffic your site is worth nothing, to calculate the value of your site you need to rely mostly on traffic. To generate traffic you need to have a lots of articles published. For example, one guy called Sean R Mize published more than 20 thousand articles on Ezine Articles and he is making more than 100.000$ a year. Can you publish as many articles as he did?
2. Use forums to get links and traffic, your articles need incoming links to be noticed by search engines, if you use forums you can be sure, you will get the links you need from your profile, from your posts and from your threads.
3. Comment on other blogs to get more links, make sure the comments are useful or the blogger will just ban you from commenting more. The comment must not say "buy from me" but actually must be an extension of the article.
4. Use paid traffic such as Adbrite or Adwords to get the traffic you need. These advertising networks are very cheap, you will be able to get thousands of visitors for almost nothing. Adbrite can send you visitors for just 1$ per thousand.