Affiliate programs are great when used in modertion. They can provide additional revenue for your site, and they can fill-in some products when you need additional products. Affiliate programs are not all equal. You need to view percentages, and how the payments will come to you. Does the program you are researching include MLM or tier payments? Do they set cookies to guarantee that the sale will be credited to your account, even if your customer doesn't make a purchase the first time they go to the merchant site? What are their minimums before they send you a check. 

Here's a list of potential affiliates that give you good suppliers and merchants.

ClickBank
Join for free! If you have a product to sell, and it can be delivered over the Internet itself then ClickBank is for you.

LinkShare Network
Join Network for free! As a LinkShare affiliate, you will earn revenue for driving sales, leads and traffic to partner sites. Find hundreds of affiliate programs from Fortune 500 and other leading businesses in the LinkShare Network.

Content Rewriter Pro.
You Can Quickly And Easily Rewrite Your Content And Drive More And More Ultra-Responsive Targeted Traffic To Your WebSite - Even If You Are A Newbie!

Add Rss Feeds To Your Website Easily!  Adds fresh content to your website instantly.

Fresh Website Content!  Amazing Technology And Increases Your Rankings!