If you are looking to find dofollow blogs to do blog commenting and get good backlinks then you should visit followlist.com where you will find lots of blogs of every niche.
if you want the blogs sites you can search on google
I search manually on google, according to my website and then comment after reading the post.
Thanks to all for sharing lots of info about do follow blogs.
There are so many ways to hunt good websites for blogs to comment on. The only thing is that it takes time, but for the benefits of all of us, I hope you will find useful thing on the so-called "DropMyLink" tool. Free to sign up and start hunting good websites which is do-follow.
You fully analyse your competitor site & notice where they are get do follow links. You will try to get do follow links from those source.