As nikita correctly pointed out, it is really irrational for a tutorial in a particular wiki to adopt Adobe Photoshop as the tool of choice. She urged to put a open sourced GIMP (GNU Image Manipualtion Program) version of that tutorial on that wiki. I aided her to install x11 on her OS X computer but no luck. I tried myself on my eMac at work with a quansi-aqua version of GIMP called Gimp.app. This is my experiemntal product.

gimpgoogle

Except the relatively dull emboss effect, relatively unmatched colour, relatively unmatched font and relatively bad craftmanship, it looks 50% alike. As a matter of fact, GIMP natively don't have the miracle layer effects like "Bevel and Emboss" and "Color overlay". I have to do it by Filter Emboss and Lighting Effect in GIMP.
All in all, my product sucks. So I haven't put my walkthough on that wiki.
I am not a photography-pro nor image manipulation pro. If you have any hints to make my product better, pls drop me a line.
P.S. when google is still a research project in Stanford, the logo of google was produced by GIMP.