The problem with affiliate marketing, like many other home business options, are the so-called gurus and get-rich-quick programs that suggest affiliate marketing can be done fast and with little effort. Odds are you've read claims of affiliate marketing programs that say you can make hundreds of thousands of dollars a month doing almost nothing ("Three clicks to rich!"). Or, they suggest you can set up your affiliate site, and then forget it, except to check your bank deposits.
I’d stick with Amazon if I were you. All of my Amazon sites only have Amazon affiliate links. If you use Google Adsense display ads on your site, you’re literally taking people away from your site for the sake of just a few cents with these type of ads. If you direct them just to Amazon, then you have a greater chance of earning more money from that click.
Your small business must pay state income tax in the state you operate in. Depending on how your business is organized, you could pay corporate tax or a limited liability company tax in addition to your personal income tax. You may pay taxes in the state the selling company is located in if that state taxes entities who earn money within their borders (even if the earner is located out of state). Your affiliate marketing company is considered a separate entity from the selling company when it comes to figuring state income taxes.