I'm not really a singer, but I've seen this question a lot so I'll give it a try. Your link doesn't work, but I assume you're talking about a raspy voice, like James Hetfield. What you do to achieve this is sing the note, and then lift the back of your throat to create another sort of vibration. To get a feel for where the back of your throat is and how to get rasp, try making an "aank" sound, like a "wrong answer" buzzer. Once you can get that sound, try applying it to your normal singing voice.
Everything I've just said has been said by Merkaba many times in this and other threaRAB, so credit goes to him. Good luck, anyway.