Just found this older guide and thought it could be interesting for you too!
Read it here
I have noticed that many people try to imitate Mac OSX Tiger's look with their current operating system. No matter is it Windows or Linux. I'm one of those people and this is my atteption to make Ubuntu Linux look like OSX Tiger. I use Ubuntu simply because it is the best distribution of the best operating system. Ubuntu uses Gnome as it's desktop environment. For this reason the guide is for only for Gnome users. It you are using some other distribution, this guide is still valid in most cases. This guide tries to be as spesific as possible, so that even newbies can follow it easily!