The only way I know, to get Windows 7 for free, is to be a student or faculty member at a university that has a site license that allows them to distribute it to students and faculty for educational purposes.
We do not allow requests for illegal download sites.
The link that I posted is from microsoft, and it seems that they will allow no-cost upgrades from Vista to 7 as long as you stay within the 32-bit OR 64-bit versions (within limits). So there may be a way to avoid extra charges for the upgrade.
Microsoft sells separate "upgrade" and "full" editions of Windows 7. The instructions that you linked to, almost certainly refer to this upgrade edition. I don't see a reference to a free upgrade. I do see a reference on page 2 to the 25-character Windows product key that you get when you buy Windows 7 either in a box or by downloading it (and paying for it) online.