Epidermis is a GUI tool to easy manage Gnome themes.I just install Mac themes to make my Ubuntu 10.04 looks Mac OX with Epidermis.Unfortunately,it doesn’t install the dock and remove the default gnome panels.

Epidermis changes the appearance of your GNOME desktop in all its aspects in one click. Epidermis ‘skins’ change the appearance of your desktop wallpaper, Metacity windows border theme, your GTK+ controls theme, your icon theme, your mouse cursor theme, your GRUB bootsplash screen and your GDM login screen theme.

Install and Use Epidermis:

Epidermis can be downloaded from here,
just double click on the downloaded .deb package to install it.

Epidermis can be launched from Applications ->System Tools menu.
In its main window click “Find more” in left,and it downloads available desktop themes.Choose a theme you want to install and click “Apply”,it take a few minutes downloading files.

Click “Installed” in left,and you will see the theme you just configured.Choose the theme and click “Apply” to apply the changes.