Have you looked into 'toast masters' in your area?
In toast masters you write your own speech under a specific topic and give it in front of the group...
Sounds scary,but toast masters is brillent for giving feedback.
I'm a member of toast masters in my area and they are lovely and welcoming,as have other venues we have visited.
Practice in front of a mirror,note your body position,and the tone of your voice.
visualise yourself talking in public and having confidence,see the whole thing in your head as a film,all positive!
Create in your sub conscience the confidence for puplic speaking and general confidence.
http://www.toastmasters.org/tips.asp.