Who knows some do follow blogs that post do follow comments fairly easily? A do-follow blog that approves comments fairly easily is www.american-election.com so just go there and find a topic even semi related to your topic and write a short relevant comment and it will probably get approved. (Yes it's mine but I would appricate some other people posting some do-follow blogs that generally approve commments - for a big list of do-follow blogs check this out http://courtneytuttle.com/blogs-that-follow)
cellularcomplements.com and superblogsunlimited.com And full disclosure, they are both mine but I don't manually approve comments, not yet anyway.