Note: I have a Facebook account (two, actually) and use it to keep in touch with people I never liked in high school. Having said that, I realize that there is a large percentage of the world that has sworn it off. I hope to convince you to set up a Facebook account, even if you never use it.
Here's the deal: like it or not, there are a ton of Facebook freebies out there just by "liking" a company. They're put out there by companies who need some sort of social network strategy but don't know how to do it, so they throw everything against the wall to see what sticks. For that reason, at a minimum, you should also have a Facebook account, even if you never use it for anything except freebies.
There have been any number of concerns about Facebook privacy and they are generally valid. No one says, however, that you have to use your real information. I have a second Facebook account and second email address that are used exclusively for freebies. I get no spam, since I don't really check that email address.
Important: Almost all Facebook freebies are of the "print this coupon for a free thingie" genre.
Bottom line: Facebook is making the internet look like the good ol' days, when everything was free because companies thought that any dot.com address was the way to riches. Take advantage of it while you can.