Abysha,
I'm glad it's given you some hope...I wish I could offer you a definitive secret that gave me the voice I have. In truth, a lot of it was just timing. I made a conscious effort to use the highest voice I could possibly muster from when I was fourteen, as I mentioned above. However, I should note that my vocal cords DID mature (though not completely), and all I did was stretch my range out a bit! You call what I did at the end of the clip my "boy voice", but I never had a boy voice to begin with! That's the deepest tone I can hit, but even that takes a lot of effort. It's not like I have two voices; I jsut have a very stretched range. Gradually stretching your voice is the best advice I can offer. Use a keyboard to set a pitch and try and base your speech off of it for a week or so. After that, move on to the next one. The voice is a muscle, and you just need to stretch it.