If you are interesting in getting backlinks from blogs where you post your comments then probably the best way is to post comments on a blog that is “DoFollow”.

A simple way to find out is to download a FireFox plugin called “SearchStatus“, this is an extremely handy plugin, not only will it highlight all the Nofollow Links on a page so that you can see what is a DoFollow link, but, it also display a websites Google PageRank, It’s Alexa rank and it’s Compete Rank.

It also have loads of other features such as showing a sites whois listing, Meta Tags, link report and much more.

So if you are serious about for commenting on DoFollow blogs then this is a FireFox plugin that I would personally recommend SearchStatus.