type in google: "*.edu" keyword http://www.google.com/#hl=en&safe=off&q="*.edu"+finance&aq=f&aqi=&oq=&fp=64df356c6a3f8304
You can search on google using specific terms as someone already stated, you can also put parameters like "logged in" and things like that to make sure you dont have to make an account
Search on google with your niche keywords and the parameter inurl:.edu and you will find .edu blogs of your interest, Leave a good comment on them with backlink so they have likely chance of getting approevd.
Google's representatives and engineers have been saying on blogs and interviews that tld has no effect on ranking unless it's related geo-targeting. .com,.edu.org etc. are all same. The only thing that changes .edu sites is that they become authority and trusted sites 'automatically' with lots of backlinks and PR.
That's not true. Unless your site is education related and matches with theme of edu site linking to you, don't expect much help. Try to get links from related site =]