Susan Cain who wrote the amazing Quiet has launched an online resource for introverts. Take the test to understand your introversion:

Given the choice, you’ll devote your social energy to a small group of people you care about most, preferring a glass of wine with a close friend to a party full of strangers. You think before you speak, have a more deliberate approach to risk, and enjoy solitude. You feel energized when focusing deeply on a subject or activity that really interests you. When you’re in overly stimulating environments (too loud, too crowded, etc.) you tend to feel overwhelmed. You seek out environments of peace, sanctuary, and beauty; you have an active inner life and are at your best when you tap into its riches.