Most people I meet are terrified of "networking".  They picture walking into a room full of people they don't know and making useless, superficial chit chat, so they can exchange business cards and make "contacts".  That's not at all what I consider to be effective networking.  It's about meeting cool new people, keeping in touch with them, and finding ways you can help one another out.  In fact, you don't even have to ever meet people face to face to network. 

One great way to begin the journey of becoming a strong networker is to sign up for an account on LinkedIn.  It's a business networking website that lets you keep in contact with coworkers, business contacts, college friends, etc.  You basically invite people to "link" into you, and it's a great way to stay in contact even when people change jobs.  One really neat feature on LinkedIn is the ability to ask and answer questions.  I have asked questions, for example, on blogging tips and received a wealth of information from total strangers all over the world, many of whom I have since "linked" into and keep in regular touch with.  I have also found lots of questions where I was able to provide helpful information to someone else.  For an introvert or someone that's shy, it's an easy and quick way to meet some amazing new people, share and gain knowledge, and develop lasting relationships.

Also, check out this cool article entitled, "Social Networking tools give introverts opportunities to connect, lift careers".