Before you do anything else, just listen to this. That's eefing, a 100-plus-year-old vocal technique from rural Tennessee that's, well, the original hillbilly beatboxing. The undisputed master of the art was Jimmie Riddle. His unique skill landed him recording* and TV (youtube) work. Want more weird sounds from the deep south? Try Hollerin & Whoopin and Ringing the Pig. *[warning: on the "Little Eefin Annie" page, avoid the "click here to hear Rolf Harris Eeefin'!" link: it's a pesky popup.
The Human Beatbox (Video). I meant this to be a follow-up to another previous thread about this specific ability, but the search page won't give me my results. At any rate, this guy amuses, entertains and scares the bejeezus out of me all at the same time. Good enough for me!