Ric - Yes there are networks and going alone. Many 'good' publishers will not even look at a self run affiliate program due to payout issues.

Martin - also think about adsense
Here are some posts on affiliate marketing that may be of interest

How to choose an affiliate program that will make you money

So you want to start your own internet business….

An affiliates guide as to why not to use banner ads

AdSense as a Business Model

An affiliate program for your website? - Some important considerations.

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