Want to get a job using social networks? Here’s how to use Facebook, LinkedIn, Twitter and Plaxo to land the right connections.

With 80-90% of all jobs filled through alternate means besides actual resume postings, the phrase bears repeating: You are who you know. That’s why social networking sites with a business edge such as undisputed industry leader LinkedIn (www.linkedin.com) are so important. At LinkedIn you are judged, at least somewhat, by the company you keep. And if that company consists of people within your particular area of expertise, be they satisfied coworkers, distant associates who’ve come to know and like you through your business dealings, or higher-ups who appreciate your skill set, the prospects are bright should an opening become available. Why? Because LinkedIn is now so elephantine and so seemingly necessary in the business world that few people of importance don’t utilize it.