We tried to use it for local services and we failed. All of the likes were coming from people who did not have anything to do with our service. It was really bizarre. I made the target audience very narrow but could not get a single hit that was a real potential customer. We switched up strategy and just asked everybody in our social network to like our page and share our service. This helped quite a bit, even though this is for free. :) Next thing we did was using meetup.com and target the right meetups with a discount campaign that worked out pretty well, this was also for free.
I have had success for those I have helped. My dad picked up quite a few jobs (he is a plumber by education) that way and we only spent around 100USD.
But I am sure there are things where it doesn't work or areas were it wont work.
With regards to asking network yes, thats the first thing I always ask them to do.
In fact I don't understand why larger corporations do not have some social media incentive program for their employers so they can help spread the word and perhaps get leads.
