How to Find Valuable .EDU and .GOV Blogs for High Value Backlinks:Step 1) Open Google.comStep 2) For .edu blogs search
Step 3) Copy/Paste the following EXCEPT really put your niche keyword(s) where it says “Your Niche Keywords”site:.edu inurl:blog “post a comment” -”comments closed” -”you must be logged in” “Your Niche Keywords”Step 4) For .gov search you can do same thingsite:.gov inurl:blog “post a comment” -”comments closed” -”you must be logged in” “Your Niche Keywords”Then, visit each blog in the listing, leave a genuine comment, and then Bookmark it under an EASY TO FIND label such as “.edu highprblogs” or “.gov highprblogs” so you can revisit them.
Source: http://publisher-tricks.us/black-hat-seo/getting-edu-and-gov-blog-backlinks