The Internet has always been an open market, but the "Social Media" sites have been taking it to a new level, now anyone can get a Facebook account, or a Twitter account and start spreading the word. These sites are being set up by anybody that wants to, and they only require an email address and some common sense.
In theory, you are going to start with a bunch of friends or followers on Facebook, and then you will announce your new site, product or information, and any body who wants to can just click on your link, and then your information is posted on their wall as well.
You also get the chance to get a little traffic from them as well, and this "backlink" effect is great for your search engine rankings and your Page Rank.
The first step is to find some people who are interested in your topic and go to some of the many social networking sites out there, these sites do not actually have to be social media sites they can also be review sites or even encyclopedia sites.
Some people are more interested in their friends, and these people will be interested in your information, and it is best to stay on their friends list, so that you don't get kicked off the friend list without warning.
You can also get traffic from Twitter by using your Twitter account, but that is a whole other topic. But the bottom line is, you are getting more traffic from a group of people who already liked you before you started your social media journey, and now they are interested in you too.
Now your work is just to stay on top of them. It's like dating - you get thousands of people on Facebook, so you better have a great story or very compelling information to get their attention.
Facebook is also great for giving out freebies, if you have something to give away then you can simply go to a community page and post it. There are also special pages for "tips" and "how-to" videos.
The more interesting you are the more they will want to visit your site, you also get likes from your friends and followers, and each member of that group has a small vote in your favour. Your site gets a better ranking from Google as well.
It really is a bit of a win-win situation. Your site gets better placement, and you get more traffic.
You get traffic from people who already like you and will like your website, and if your site has valuable information they will visit it. You get better placement on Google and Facebook.