Good comment Jason, at some time in the future Amazon may decide they have so much market share they don't need affiliates anyway. I mean, if you're just sending them people who are already Amazon customers there's not so much benefit there for them. Or they may decide to only work with select HIGH QUALITY affiliates and the average "affiliate site" owner will not be chosen.
Amazon makes it fairly easy to list and sell old books, games and devices on its marketplace. You can make more than just a few bucks If you have pricey textbooks from college. Be sure the books are in good condition. You'll get negative reviews if you attempt to sell books that are falling apart or games that are scratched up. Remember, be upfront about any defects, no matter how small they might be and no matter how few people might readily notice it. 
In April 2008 the State of New York inserted an item in the state budget asserting sales tax jurisdiction over Amazon.com sales to residents of New York, based on the existence of affiliate links from New York–based websites to Amazon.[45] The state asserts that even one such affiliate constitutes Amazon having a business presence in the state, and is sufficient to allow New York to tax all Amazon sales to state residents. Amazon challenged the amendment and lost at the trial level in January 2009. The case is currently making its way through the New York appeals courts.

Affiliate marketing currently lacks industry standards for training and certification. There are some training courses and seminars that result in certifications; however, the acceptance of such certifications is mostly due to the reputation of the individual or company issuing the certification. Affiliate marketing is not commonly taught in universities, and only a few college instructors work with Internet marketers to introduce the subject to students majoring in marketing.[41]
Forms of new media have also diversified how companies, brands, and ad networks serve ads to visitors. For instance, YouTube allows video-makers to embed advertisements through Google's affiliate network.[22][23] New developments have made it more difficult for unscrupulous affiliates to make money. Emerging black sheep are detected and made known to the affiliate marketing community with much greater speed and efficiency.[citation needed]
Amazon has spent years perfecting the art of online selling and you’ll learn a lot about online marketing by observing how they do it. They constantly test different ways of promoting products and have evolved their site quite a lot over the years. See what widgets they use to promote related products, watch how they use reader reviews, and see the way that they describe products.
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