You need to think more like the people your targeting and go after the pages you think they might like on Facebook, or public figures that play a big role in the community you are promoting within.

The most important step is to not over think and just get a basic demographic audience to pitch your ad's too. Don't drill down too deeply as in the beginning you may be loosing a good amount of traffic. Perhaps try running some ad's for likes on a Facebook page in the beginning as this will run cheaper and means you can test the traffics engagement.

Then create multiple ad's splitting up this traffic until you've figured out the group that is most likely to make a purchase or sign up.