A second kind of advertising source are networks beyond Google. There are two main types of networks: ad networks and affiliate networks.
Ad networks. These are companies that you contract with to display their clients' ads on your website. They may pay you on a CPM basis (perhaps 50 cents to several dollars per thousand ad displays — or less), or they may pay on a Cost Per Click basis. Search on ad networks and you'll find lists of these.
Some of the better known include ValueClick, AdBrite, Burst Media, Casale Media, Kontera, Chitka, Tribal Fusion, and Bidvertiser. Some ad networks are focused primarily on one sector; others offer ads across many industries.
The problem I've seen is that ads aren't usually closely targeted to your content, but only to your general industry. Consequently, the click-through rate tends to be lower and your revenue is lower. If your website isn't highly targeted on a high priced commercial niche, however, an ad network may be your best source of ads.
Affiliate networks. We'll consider affiliate marketing in another article in this series. However, affiliate networks fit here, since they offer display ads from many advertisers.
The major difference from ad networks is that, while ad networks usually pay on a CPM or CPC basis, affiliate networks tend to pay primarily on a CPA (cost per action) basis, when a purchase or lead results from the click. Search on affiliate networks to see lists of these. Some larger affiliate networks to explore are: CJ (Commission Junction), ClickBooth, ClickBank, Shareasale, and Linkshare.
You can typically choose the ad and ad sizes you want to display on your site as well as the advertisers you think will provide the best revenue for you. However, the individual advertiser may want to approve your site before allowing you to place its ads on your site.
Bottom Line: Try to select only those ads which are closely related to your high placed keywords on the search engine, otherwise i am afraid, all your efforts to earn big money online will end in fumes.
