The Social Media Play
The biggest mistake you can make regarding social media is considering it the ultimate spam distribution system. As the term "social media" implies, people using systems like Facebook, LinkedIn, Twitter, and YouTube are leveraging text, sound, and video to engage others on the social front.
Social media is not about the hard sell. It's about expanding and impacting networks. With social media you should have a three stage goal in mind:
Get access to networks

First, you should work at gaining access to networks. Social media participants frequently joined networks based on interests, their career, and their aspirations. Lurk for a time on social media venues and discover the networks most related to your core competencies.
Expand your network

Some might remember that old commercial for a shampoo where one customer tells two friends and she tells two friends and so on. Gaining access to one network many times makes gaining access to other networks possible, geometrically increasing your reach. LinkedIn's first, second, and third tier networks is the most obvious example.
Raise your profile within the networks

The final goal for social media is raising your profile, with the goal of becoming a key "node", an opinion leader, or someone with a reputation for being an early adopter. Consider your area of expertise, you niche, and showcase that. For example, if you're great with the one liner quips and plugged into emerging technology, you might start a Twitter account offering a "headline clipping" service showcasing the latest technology.
As users in your network go to you or pass through you, some will stop, investigate the person generating the content, check out your profile, and eventually investigate your web site.