I use a piece of software called "Fast Blog Finder". It's gotta be the worlds best blogging tool on the planet. It essential searches there huge database of blogs and will sort by no follow / do follow. Check it out, it will save you ton's of time.
I found this method really easy and very helpful...better even than activating a nodofollow FF plugin! Rather than getting all the links differentiated into do-follow/no follow, this method helps in ascertaining the quality of only the link situated in our area of interest! Regards, RightMan
I just use the FireFox addon, and CommentKahuna which is a fantastic free commenting tool that filters out NoFollow blogs and even tells you their pagerank. Look it up, great way to build backlinks
To find dofollow and nofollow liks, i can use seo quake and searchstatus tool form mozilla addons to firefox it is really very easy to find nofollow links.
use this on Mozilla Firefox https://addons.mozilla.org/en-US/firefox/addon/321 this is fast way to find site is do follow or nofollow ..also You can check the sources code