The first option is to use paid services.
From my opinion best of these paid services is BoostLikes! I really recommend you to use this one.
The other best part of this site is that you can also get free 200 likes preview for your site and if you like the service you can also buy the service.
The second option is to organic setup your fan page
By organic setup i mean to use important unique keywords for your site, to use the keywords that are most searched on Facebook, and of course to use unique name. Search on Google for more informations about this topic.
Third option is not that recommended but it works - to use like exchange (automatic) sites.
Here's how this kind of websites work: you collect points by watching Youtube videos, liking Facebook fan sites, following on twitter etc. After that you put your own fan page's link and you spend that points to get likes. I don't recommend this option because the likes often are not real and they are only for look.