Search for blogs that cover similar topics. Use a search engine and the search bar on blog hosting sites to find blogs that cover your topic or related topic. Read a few blog posts from the most popular ones, that show up high on the search ranking, have the most comments, or display a readership of 20,000 or more. Get an idea for how much interest and competition there is.
Just be aware that affiliate marketing with the wrong company can damage your brand. For instance, I started my blog w/ Blue Host because of Pat Flynn’s recommendation – which I am sure he was paid for. I am now on day 5 of my site, and e-mail being down, with NO estimate from Blue Host as to when it will be back up. As a consequence, I wouldn’t buy a thing he suggested or endorsed, because of my experience with someone he put his seal of approval on. Blue Host has a HORRIBLE reputation among the community, and I even wonder if anyone would “recommend” them unless they were being paid.
Notice that I avoided putting a specific dollar figure on the amount you can make from blogging. It will come down to your work ethic, your skills as a writer, your ability to generate targeted traffic, and plain old good luck. It’s a bit like baseball: everyone played it as a kid, only a small fraction make it to college ball, an even smaller number become professional, but only the cream of the crop makes it to the majors.
Within a month, I had On Moneymaking off the ground, and within two months, it was getting 2,000 visitors a day and Performancing nominated it for the best business/money blog of the year. A couple of months after that, Brian Clark asked me to become the Associate Editor of Copyblogger, and so I sold On Moneymaking for five figures and went to work at one of the most popular blogs at the world.
Now, once you and I have taken advantage of that info. (and I am still in the process of launching) then we will be in a better position to either thank Jon or criticise him. Of course, timing is almost everything but with the amount of free flowing, easy to read, writing that Jon provides, which is the hallmark of all good communications, plus incorporating such useful content, then I like to think that if we could follow that example then eventually we (yes, you and I, Bill) would be rewarded with fans and finance.
Once you setup your account on AdSense you will be given a code to add to your blog. This code will automatically display advertisements on your blog from companies who are part of Google’s advertising network. You may see ads from small companies related to your topic, or you may see ads from large companies that are completely unrelated to your topic.