Pheeds.com

This video shows a source for getting FB insterests that isn't available in the FB Ad Center. You need to have a FB Developer account (free and easy and then install an app. The video shows you how. It comes up with some pretty good info that can be useful in a lot of ways...

Increase Profits By Using Hidden Facebook Ads Targeting
 
https://www.youtube.com/watch?v=xwC--SJI2gQ