Set reasonable expectations for earnings. You've only invested $20. You're going to make 5 percent on most products. That means that you need to sell $400 worth of stuff to make back your investment. You get credit for purchases customers make while at Amazon besides just the product you linked to, so it's not as hard as it may sound. It won't make you rich, but it's not hard to be profitable, and the income builds over time.
Research selling prices of items similar to yours. Look up completed sales or current listings of items similar to yours. Find the high- and low-end prices, and price your object around the median price level. If you want your item to sell quickly, price it at the low end. The condition of the item also affects the price. Items in poorer condition should be priced at the lower end. Also, consider how many listings there already are of items similar to yours. If many similar items will be competing with yours, you may have to set the price lower to get the sale.
If you're not technically inclined at all, register your domain wherever you set up your hosting. Otherwise, you can save a few dollars by choosing a lower-cost provider. This is not a big deal for one or two sites, but it can be for 10 or 20. GoDaddy is a good option because it offers great domain management tools and at a low cost annually. One of the least expensive and reputable in the market is 1&1. Prices start at the low end of the spectrum for the first year with increases, sometimes significant for each subsequent year, depending on what plan you choose.
The other type of Amazon affiliate link I use is when I’m mentioning a product in passing and/or a new product is announced. For example, when Nikon announced the Nikon D300s we immediately posted about the news because it was a notable and anticipated camera announcement. The camera was not yet available in stores and we were not able to get a review sample yet – but it was available for Pre-Order on Amazon so we linked to it.
Affiliates can be found all around the business world. In corporate securities and capital markets, executive officers, directors, large stockholders, subsidiaries, parent entities, and sister companies are affiliates of other companies. Two entities may be affiliates if one owns less than a majority of voting stock in the other. For instance, Bank of America has a number of different affiliates around the world including US Trust and Merrill Lynch.
You can sell your ebooks through Amazon's Kindle program or Apple's iTunes Connect, which gives you access to a large majority of the digital-book reading market and the barriers for entry are incredibly low. You don't need to invest lots of money to make this happen, but you do need to invest lots of time, not only in writing the ebooks, but in marketing them as well.
No matter what method you choose to make money online, understand that you might be able to make some money fast, but for the sizable returns, you'll need significant sweat equity. However, a year from now, you'll be happy you started today. Remember, time is far more valuable than money. Focus on creating passive income streams that will free up your time so that you can quit the rat race and focus on the things that matter.