Commenting in blogs

in this site you cannot.. add links to your site or blogs in the comments.. especially if your site have the same purpose as this site... and there is not much sites that allow to do it either...
However.. in most sites links are allowed in signatures. It will be counted as back links.. but it won't bring your page rank much high..

There is a similar topic going on, if you would like to take a look at it:
http://www.webicy.com/index.php?topic=5.0

you can use the sig links in this forums and get backlinks. Try getting backlinks for sites similar to your niche

Most blogs use no-follow tags on comments. This means your link will not register as a backlink. If your comments are useful, they can generate traffic regardless.

Commenting in blog is a good way to get link back but you have to check is there any nofollow tag or not?

I've used programs like comment sniper and comment hut with certain success. However to really make your comments count they must be on a web that is close or in your niche and preferably do-follow.

If you are commenting on do follow blogs and that blog is related to your theme and having high page rank too, then there are more chances to be counted as back link of this comment link juice.

Comments are welcomed by the vast majority of blog owners and irrespective of whether the links are dofollow or nofollow you can get some traffic from them especially if your comment is a valid one that adds something to the debate or article.