[littleboy]

Social phobia = fear of being rejected, fear of what other thinks about you.
Summary: Fear.

Fear of being rejected usually occurs in people who had though childhood (Its amazing, how our past(childhood) affects our personality in maturity).

You need to overcome fear, not to overcome the 'anxiety of speaking in the public, or socializing or similiar'.
Fear is 'incorporated' in us in the process of programming (thats how i like to call that period of growing up(im a computer programmer) age 4-20 or so).

Fear is induced by looking at the future. What will happen in a day, or in a hour ... after i finish a speech in front of 20 people, or 1... if you 'project' in you mind that he is more important then you, like most of people do when they confront a boss or someone who allegedly have more authority over you.
Ok, first of all... why is he more important ? He gave you the job ? Screw that. The most important person for you, is .. you. You be what you are.
The problem is we all act, or where acting .. in some degree, and we'r afraid of being discovered. Of our social status being 'downgraded'.
Almost every person on earth have multiple identities. One that they are projecting to other people, and the one when theyr are alone with themselfs.

Second thing.
Fear of other people who have equal social status like you.
Why you should fear them ? You think they are perfect ? No. They arent.
Humans are far from perfection. We all have strong points, and weak points. I suck at geography, so i don't give a f if someone think im stupid, since I know something that he doesn't. So we'r both stupid then, when you look at it - fine with me. If he judge me, then I don't want to be near that person, since he is a bad person. I would rather live alone in isolation, then with those kind of people.

Third thing.
Job is like a old fashioned trade.
I will give you the carrots, you give me 10 bucks. You need my carrots, so you gotta pay me. Of course, you can buy them from someone else, but you already hired me for the trade. If your not satisfied, I will sell them to someone else, but you will not pretend to be in charge of my life and my future, I will not fear you, since this is a mutual benefit.

Conclusion.
To get rid of fear, you need to get rid of your 'ego'... which is almost impossible in short time, but you can contain it a little.
Your ego, your thought, is crippling you. Preventing you to be functional.
We learned to fear. Im not talking about psychical fear, of being hurt, thats instinctive, rather.. im talking about psychological fear which we learned, like we learned to be ashamed of nudity and stuff like that.
You need to stop thinking. Thinking about the future. You need to have a disciplined mind, silent mind.
Be yourself. If you don't know who you are, work on that. Meditate, follow your thoughts, dont judge them... what ever they are.
Don't think. Meditation is not sitting in a room concentrating on sandy beech and sun, palms etc... those who do that, cant escape the restraints that the system/society forced in us, rather it is not thinking at all, just observing. If you start thinking your ego will come in game and censor part of your unique individual characteristics, that you may not like.
You can only overcome them if your just an observer, not a judge.
Our thinking is responsible for fear, for wars, for Gods for division between the people, for prejudice, for pride.

Key word is Love. Learn to Love yourself, to respect yourself, then you will not fear. Like I said, if someone don't accept you, you are better not to have that person in your life, you are not loosing anything.

P.S.
I started mentioning meditation, since I believe its the only effective way.
You can be in situations where you will not encounter fear, but a change or something new will induce it again. In a month, you will not fear your colleges, and similliar, but you will during your life encounter fear many more times, unless you eliminate the fear in the core. In your subconscious.