One way to create an incentive for fans is to provide a download of some sort for liking your page (see free welcome templates and additional ideas at The Social Networking Academy, through the banner above). Also, you can participate in "Like" Ladders, Silent Tagging and other exchanges through Facebook and LinkedIn to grow your fan base (although these exchanges are less likely to get you in front of your specific audience).
Other strategies for generating Facebook fans are provided here:
Good luck in building your Facebook Fan pages, and please also like ours here:
(Please note, we haven't followed all the strategies and suggestions for beefing up our own Facebook page, but we're working on it!)