With any niche site I create, I create a facebook page for the site. Do not link this site to your personal account! One, it will make your personal facebook experience rather annoying and two your competitors will know every site that is yours (bad).
Once I have a good profile built, I create a fan page. Here's the trick to it that most people don't do: Most create a fan page for the site, so 'click here to become a fan of examplesite.com'. That just won't work well unless you have a great site (please note I create a fan page for my site, but this is not the main source of traffic from facebook).
I create a fan page for something specific to the niche that is popular within the niche, then as I add posts and videos to the page I link to my original business page. Make sense? I also tag the original page whenever possible.
This might be confusing, so let me give you an example, using golf (since everyone reading this has probably promoted in the golf niche). Instead of creating the 'improveyourswing.com fanpage', I would create a fanpage for 'finally getting a hole in one' or something like that. People are much more likely to become a fan of it, thus making it 'go viral', which gets way more eyes to your business page, and eventually to your website.
So, to clarify: Facebook page for your site, fanpage for your site (just so it's there really), fanpage for 'happy' thing related to your niche. I try to at least post on all 3 pages daily (takes 15-30 minutes) and add two videos a week to the 'happy' fan page. By doing this, and linking to my site and original page, I'm able to get a ton of visitors for free! Great for those who need a break from writing articles :-D Hope it helps someone!