For the benefit of other writers and to reinforce the steps for myself, I'm going to lay out a step by step process to identify, research, write and monetize a product based article. Hopefully this article will be something you can print and put on your wall in front of your computer.
The example article is called What is Rice Bran Oil? and was published on Infobarrel.
Step 1: Get a Product Idea
There are obviously millions of products to write about, but I prefer to look for something that is more unique and not written about by everyone already. It may seem counterintuitive to pick a product that is not very popular in the market, but remember that there is far less competition for keywords on a niche product.
In this case I was in an Asian grocery store and spotted a bottle of rice bran oil. Never heard of the product before but it sounded healthy so I bought it. When my Asian wife saw the oil she asked what it was - this told me the product was not that common even in her country where they eat tons of rice. These experiences helped me see the oil as an opportunity.
Step 2: Check a Logical Search Phrase
I went to Google and entered "What is Rice Bran Oil?" and only 610,000 results came up. Compared to a lot of searches that is nearly nothing. For example "What is Corn Oil?" brings up 17,400,000 results. The shorter search term "Rice bran oil" brought up just 669,000 results.
Step 3: Analyze the Search Results (SERPs).
In this case the top result was a wikipedia article and the next result was a small .info site about rice bran oil. Than I found a cooking site, a health advice site, an old science daily article, a rice bran oil manufacturer site, a health food store and a product review article.
None of the first page results were titled with my search query "What is Rice Bran Oil?" (no exact matches) and interestingly, Google did not highlight my whole search phrase on any of these pages, although some certainly would answer the "what is" question quite well. So few sites actually include the exact keywords I was thinking of.
If the chosen search term is a search term other searchers use and no webpage actually targets that search term as a title, you may have a winner.
Step 4: Check the Google Ads
If there are no related ads beside your SERPs than its going to be hard to make money with the topic. In this case there were a few unrelated (Alberta tar sands information - wrong kind of oil!) and a few highly targeted rice bran oil ads shown. Not perfect but not bad either.
Together Steps 2 through 4 should take a few seconds once you know what you are looking for.
Step 5: Check Google Adwords Keyword Tool
Over at Google's Keyword Tool, sign in so you can get full functionality. I plugged in "rice bran oil" into the search box. In this case I felt I had a targeted winner - a commercial product made by multiple manufacturers without a lot of information out there about it. I therefore checked the "Only show ideas closely related to my search terms" box to sort out unrelated results.
I sorted the results by Global Monthly Searches and found that "rice bran oil" and "what is rice bran oil" both came up with 27,100 global monthly searches. So my guess at what people might search was dead on correct.
Next I looked at other related keywords and noted them for use in the article. Several of these became bolded subheadings in the article.
Step 6: What Are the Keywords Worth?
Sorting by approximate CPC gives an indication of what an advertiser can expect to pay for that keyword. As a publisher we earn 68% of what the advertiser pays Google. My search term is not very valuable sadly. However several low volume related search terms have better CPC values. One or two of these higher value search terms became bolded subheadings in the article and the basis for paragraphs. Hopefully the use of these words will bring higher value ads.
Step 7: Check Amazon
I was pretty confident that Amazon would carry the product, but I checked anyway. Kept the Amazon tab open for the next steps.
Step 8: Setup the Title, Keywords and Amazon Links
Using what the keyword research told me I created the title and added keyword appropriate tags. I also plugged in rice bran oil and the grocery category for the Amazon widget (based on my checking of where to find the product on Amazon)
Step 9: Write the Article
In this case I got most of my info from the Wikipedia article, rewriting everything into unique text that is hopefully better than the Wikipedia content. I supplemented with info from several other sites in the top 10 search results, again, pulling facts and placing them in my own words.
I added completely unique content on where to find rice bran oil, noting it is hard to find but that it is available from Amazon.
Step 10: Add Affiliate Links & Interlinks
In this case I've got no other related article to link out to, but if you do, add the appropriate links.
This article is all about a physical product, so I linked to two different Amazon search result pages contextually. I left the Amazon search box open for this reason. Amazon may not be the answer every time but in this case it makes sense.
Step 11: Add Some Visuals
I pulled a couple of product photos off of Amazon and inserted them in the article. I needed to resize them and change alignment to "left" using the Image button to make everything flow correctly. Because of some bulleted lists and a table inserted I also needed to move the images around several times before I was happy with the overall flow of the content beside the ads.
You can, and maybe should, use the media module provided to insert photos, but in this case I did not want to break up my text, I prefered that the text flow around the images and I needed to overcome some unusual layout issues. Read this advanced article on using images to your best advantage.
Step 12: Publish and Double Check
Of course I proofed and spell checked the article before publishing. Once up, check that everything looks as you intended. Remove any weird spacing and shift elements around so that the page looks good. Here is the finished rice bran oil article.
You should also look at the related article area. If the articles are not related (which throws off your SEO) consider adjusting the infobarrel tags until the related articles are a good match.
Step 13: Promote & Interlink from Other Articles
There are lots of ways to promote your article, but that is beyond the scope of this guide.
It may make sense to write articles around related keywords (you already have the research done) and interlink the articles together. Also add contextual links into other related articles you already have published.