Vas PC Questions.

Hello fellow gearheads.
I would like to install Vas PC on my Golf 4 but i'm having some difficulties.
First, i don't know from where to download Vas PC and how much does it really cost?
I'm also wondering about the installation process. How can i install Vas PC on my lap top? On which OS it works the best?
And at last, do i need some special hardware and interface in order to apply Vas PC on my Golf 4?

Any thoughts?
Thank you in advance.

Anyone? Just need simple answers.

No one -_-