If you are doing research on a product you are looking to purchase, like a Click bank product for instance, all you need to do is perform a search using keywords like "scam" review" or "reviews". A good example would be to type in name of the product ex. "new product review" most times you will get sites that are affiliates promoting that certain product and a lot of times they will have a high page rank. One good way to do this is to do your search in the Firefox browser that has the page rank checker add-on, this will tell you how high a page rank you will be getting from the comment you are leaving. Many times while doing research you have anywhere from five to ten opportunities to leave comments pointing links to your blog. When you leave your comment make sure that it is within the scope of the article. A good example would be, "Thanks for the information, I am looking into purchasing this course" by doing this, most times, the webmaster will approve your comment in the hope of getting the sale. Most times you will get one link from leaving your website name.
A good way to get a second link is by leaving an anchor text embedded in your comment. An example of this would be, Good Post! this will show up as "Good Post!" (without the exclamation points) and will give you two backlinks to your site or sites if you want to point the anchor text to a different site. By building back links while surfing you can get two things done at the same time and in no time get quality backlinks built pointing to your website. If you apply this system you can easily get 40 or more backlinks every week. If you are looking for a way to post comments other than doing a Google search I suggest a free website called dropmylink.com which is one that I use. Here you can choose a specific keyword to find similar websites in which to post your comment and also get good links. They also have many different categories to choose form so you can get a good variety of links. keep in mind that when you are surfing do not pass up the chance to get some good backlinks and if they are on a site with a high page rank all the better. Good luck in your posting.