When Social Networking Guinepig first came to fruition I mentioned a few social networking sites which I joined to help me on my journey to Web 2 - one of which was LinkedIn.
This is a great networking site which has loads of potential. It provides the opportunity to build relationships with professionals all over the world.
You can even use LinkedIn to ask a question. These questions are answered by members with expertise or experience in the particular area you seek to find more information on.
LinkedIn can be a little daunting to begin with.
Common Craft (I am a great fan) have developed a video for LinkedIn which helps you "get the most" out of LinkedIn