When I first got into affiliate marketing I read two books that I can strongly recommend if you want to learn how to become a successful affiliate marketer.
The first one is Rosalind Gardner's "Super Affiliate Handbook" http://www.superaffiliatehandbook.com/
...and the second one is James Martell's "Affiliate Marketer's Handbook".
http://www.work-at-home-net-guides.com/
I found both really useful. Rosalind's book is more basic, while James's book is focused on an own strategy that he has worked out that rely mostly on search engine traffic.
Personally I would probably use a mix of their methods when building an affiliate site.
James Martell actually had a few of his sites penalized by Google, which is the reason why you shouldn't rely on search engine traffic alone. However, I believe he said he was using some technique that he's not teaching in his book, and I haven't heard of any readers who've got penalized following his strategy. It's the linking part that you should be careful with. Don't ever crosslink sites that don't fit together, and you shouldn't have any problems.
You can view some video and listen to some audio on James's site for free that is really inspiring. Here's the link: http://www.work-at-home-net-guides.com/pop...ideo-files.html
Check them out. If you're planning to start a career as an affiliate marketer I can definately recommend these two books. James's book is a little pricy, but at least check out the clips!
Jakob