I know it’s part of Shareasale, but Wayfair might be worth mentioning. They’re a huge site (mainly home & garden and pets) and actually have a better selection than Amazon in a lot of categories. I used them successfully on an old home furnishings site I had since Amazon’s selection of products was lacking in this particular niche. 5% commission on everything with a 30-day cookie and easy to get approved from what I remember.
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.