I need a Voice Coach!

LOL, to those that know me...or even those that have seen my videos, you will think this is funny. After all, the last thing I should need is help in projecting my voice...I am loud, everyone can here me easily all of the time but there's a problem...at the end of a class my throat hurts, at the end of 2 classes in a day or 2 nights in a row I have almost lost my voice and chances are I am going to get sick.

Yes, I can be loud and I can project my voice well but I am not doing it right. There is a way to speak loudly without yelling, etc. It is the way university lecturers speak every day to a hall filled with hundreds of students...and they don't go home with sore throats from it, or losing their voices. I have a very hectic teaching schedule coming up in the UK and Canada and I really need to be able to do more than 2 classes in a row without losing my voice...so I am in need of a voice coach, something I thought I would never need LOL!

Take care,
Chanta