That being said, here are a couple of links.
Diaphragm Breathing/Speaking: http://www.roleplayingtips.com/readissue.php?number=3
Khargyraa Techniques: http://www.youtube.com/watch?v=uCom9ZCJAmE
The best tip for the Khargyraa stuff is just to watch that video and maybe this one and then wing it for a while, trying to get the sound right. If you manage it, try just saying some stuff in a normal voice and note the difference. It is immediate and surprising.
This link is nice because the guy is such an amateur! He clearly learned, like, one technique (probably from youtube) and then posted his immediate results on youtube, so it's a good starting point. http://www.youtube.com/watch?v=X54KBdi5_xg
Thus spake Eliezer:
It seems that many here might have outlandish ideas for ways of improving our lives. For instance, a recent post advocated installing really bright lights as a way to boost alertness and productivity. We should not adopt such hacks into our dogma until we're pretty sure they work; however, one way of knowing whether a crazy idea works is to try implementing it, and you may have more ideas than you're planning to implement.
So: please post all such lifehack ideas! Even if you haven't tried them, even if they seem unlikely to work. Post them separately, unless some other way would be more appropriate. If you've tried some idea and it hasn't worked, it would be useful to post that too.