Add more people, not too quickly though or you will get banned, eventually when you have a lot of people added you will find more people adding you
Go to mafia wars application, post on discussion boards in one of the "add me topics" you will get tons of requests.
I have heard a couple of people suggest fiverr and I have tried it myself and not bad. The only issue I had with it was that traffic was not targeted to my particular niche.
If you join a large socal network or firum in your niche, you can find these same members on facebook. You could even set up a thread about exchanging facebook addresses. That way you will have friends that will actually be interested in what you have top say, rather than unintersted random strangers!
Awesome, did'nt of this before. This is a superb idea and I am going to try it now. I hope it will work with DP
Find people from your friends. Just keep on adding although some considerations should be taken because there are some abusers on Facebook.