Avoiding people you like is not a good idea because this avoidance behavior just reinforces itself. Typically, it can go like this: You want to approach someone, but you can't, so you get angry at yourself and tell yourself, oh, he's probably a jerk anyway. And who wants to hang out with jerks?

First off, examine your thinking. Ask yourself: What are the thoughts I have when I avoid the guys I like? Is it a fear of rejection? Visualization might help. You must have had some positive experiences--maybe someone approached you once, flirting, and you responded well. Think back to those times to remind yourself of your potential.

Actively reminding yourself of your positive qualities and strengths can also help to make you feel more confident. You say you have a lot of friends. Think about what they like about you. Also, picture yourself talking to someone you have a crush on. Practice what to say, if you wish, so you won't be so tongue-tied the next time you see him.

After you do your visualizations for awhile, give yourself a challenge. Pretend that you're NOT shy. Nothing too elaborate, just small actions. The next time a funny thought occurs to you when you're around an attractive guy, just smile and say what's on your mind. You don't have to stay and have a long conversation--these are just baby steps. Just smile and walk away...or stay, if the conversation takes off. You never know. As your confidence builds, you can stay and talk for longer and longer intervals.

You can also practice things like eye contact, introducing yourself and making small talk with people you're NOT so attracted to, just to get in the habit of doing it. Again, practice, practice, practice. Breaking out of your ingrained patterns can make a big difference in boosting your confidence.

Remember, you're not alone. A lot of girls struggle with issues of shyness. For example, check out Linda's story Confessions of a Shy Girl. She might have some tips for you as well!

Good luck!