gstyle is a full gnome theme manager this software try to concentrate every possibles themes types in one main window with easy install of new themes form gnome-look, deviantart, customize.org... or by direct download from the software.
Install gstyle in ubuntu 10.04/9.10
Open the terminal and run the following commands
sudo add-apt-repository ppa:s-lagui
sudo apt-get update
sudo apt-get install gstyle