I believe the first thing you need to do is address your shyness. There’s a bunch of tips in this article: http://hubpages.com/etiquette/MyShyness.
Don’t stress about talking with the guy you like. Just take it easy and take each step in the Shyness Remedies article and you should be ready to chat with him soon.
I encourage you to be more realistic about approaching the guy. He’s just a guy you like. You like him, which is not the same thing as loving him. So don’t put so much pressure on yourself. This is just some guy we’re talking about, not the love of your life.
I understand you probably feel left out if all your friends have boyfriends but I hope you’re not chasing a guy just because your friends have boyfriends. When you do get a boyfriend, it should be for all the right reasons.