AdSense Secret Revealed:

If you have your own website, you can sell ad space to  Google in your  web pages making AdSense money from Google.
 
In the past there we had the Googel referal program.  Then, people can earn more by spreading the word about AdSense and Firefox through referrals...  The Google Referral Program had retired for some time  Now people can only earn money with Adsense from Google.
 

With regard to Google AdSense I would recommend  Joel Comm.   Then , who is Joel Comm and why should you listen to him?  

Quote:

" If you are reading this page and want to make more money with Google Adsense, you are in good company! My name is Joel Comm, and I've been an Internet entrepreneur since 1995. I run a series of family-friendly web sites and continue to earn a generous income online.

In 1997, a company called Yahoo! purchased my game site, ClassicGames.com, and today it's known as Yahoo! Games. My face is seen hundreds of thousands of times daily in the form of a cartoon avatar at the Yahoo! Games game tables.

Through the years, I've built dozens of web sites that welcome thousands of visitors each day. I've found many ways to generate revenue online, but I wasn't prepared for the revolution that would take place in the form of Google AdSense.

In June 2003, I signed up with Google AdSense, and did what many others do. I simply took the code from the AdSense site and pasted it onto my web site. And then I did what many others undoubtedly do as well. I wondered why I wasn't making any money.

But then I got smart. I suspected that I was leaving money on the table, so I began testing my AdSense code using completely legitimate means. What I found changed my life.

From just $30 per day, I had shot up to $500 PER DAY with just a few easy changes in my spare time. I looked at my incredible 5-digit check and thought I must be dreaming. 'There has got to be a mistake", I thought. "Google is going to call me up and ask for their check back." But the call never came.

Deep down, I knew it wouldn't. Each time I logged into my AdSense account, the proof was right before my eyes: My AdSense stats! "

Click here Adsense Secret by Joel Comm (Highly Recommended) to see the real, recent screenshot of Joel Comm 's AdSense stats page. With Google's permission, Joel reveals how much  he ismaking with AdSense. But they've asked Joel to keep details of CPM and CTR private, so he has blacked them out in order to comply with Google's terms of service.

Recommend Highly reference books:
Google Secrets
Guide to Google Adwards