Hi DSL, unfortunately there is no magic way of doing this. There are a few ways of getting likes and I will list them below.

White hat solutions would include:
Paying Facebook for an add
Inviting your friends to join the group

Black hat solutions would include:
Making a fake Facebook account, friend requesting mass amounts of people and then inviting them to join your page. Hint, people like hot women.
Use tools such as this

Like all aspects of web marketing, this takes time and work.

Good luck with your project