There are literally 9-10 of these posts a day, use the search button. Get a firefox plugin to check or look at the source.
Look at the page source, if previous comment's links don't have rel nofollow before them then its a do follow blog.
I don't know how to find but this is the list some one shared on DP http://blog.crazy-master.info/software/do-follow-blogs/
The firefox plugin is the best way to tell if a blog has dofollow enabled. http://www.zacharyfox.com/blog/free-tools/nodofollow-a-firefox-extension