I don't recommend bots, they have no benefit to your business. You need people talking about you on Facebook. I have found the best method is Twitter. After playing around for the last few months, I finally mastered growing a list on Twitter pretty quickly. The one thing I haven't mastered is getting these people to buy my products so changed tactics and get them to like me on facebook. Twitter uses are generally active in the social media world and communicate about my brands on Facebook for me. This helped me build my network to get sales through Facebook, potentially even those same people I couldn't monitze on twitter.
Hope that makes some sense to you.