I don’t rely on anyone’s dofollow blog list to search for new dofollow blogs. Most of the list available online are not updated for months or years. Huge number of dofollow blogs change to nofollow daily. Verifying dofollow blogs frequently helps to create good list of dofollow blogs. Using Google Custom Search Engine will help us to find nofollow easier. Randomly search for any keyword from custom search engine (list of dofollow URL you have collected) and verify the comment links are dofollow or nofollow.
There are only one method I prefer to use to find high PR dofollow blogs. That is manually search from google or yahoo search engine. Mostly, top results for any keyword searchedwill have high PR. Going trough top 1,000 search results for any keyword will deliver hundreds of new dofollow blogs to our list. Continue doing this for as many keyword as possible. At the end of the day, you might able to collect hundreds or thousands of verified high PR dofollow blogs. Commenting on high PR dofollow blogs might help you increase page rank. Better if they allow keyword in name section of commentators which helps tremendously in google SERP ranking.