Use affiliate programs.
Monday, December 3, 2007 | | |With affiliate marketing, a company agrees to pay you a commission for helping to sell their products. Visitors see the company’s ad on your Web pages and, if they click through to the company’s Web site and do a particular thing, you’ll get paid. The particular thing the visitor has to do varies; some affiliate programs pay per click while others pay per lead or even per sale. These are four of the biggest (and most established) affiliate programs on the 'Net:
Amazon
Linkshare
ClickBank
Commisison Junction