I had a go at some facebook ads over the last few days. Not expensive, as you can pay per click.
Since last monday, I have had 7913 people see my ad an average of 9.4 times. Of those, 24 people have clicked the ad to view my site, and the number of people who 'like' my page has grown from 4 of my friends, to 24 people, some who I don't know at all.
Just yesterday, I changed my ad to mention that we have weekly specials, and added my phone number, so people don't even have to click on my ad for my contact details.
You can also specify your target audience. I chose to advertise to anyone using facebook, who lives within 10km of Toowoomba, which accounts for roughly 33,000 people.
You can be very specific with your targeting, using location, proximity to location, age, marital status, gender, ***ual orientation, language spoken, interests, level of education, and even which company they work for, provided they have input this information on their profile.
The feature also gives you fairly detailed reports on demand.
I think I'll just keep going with it until I either reach the full 33,000 of my target audience, or get some jobs, or go broke
It seems the number of people liking the page would grow exponentially, as it becomes visible on the pages of more 'friends of friends'.