[Discover] HowTo: theme your desktop - Ubuntu Forums http://ubuntuforums.org/showthread.php?t=203093
(ubuntu theme desktop tutorial) 
[Discover] GNOME-Look.org http://www.gnome-look.org/ (linux gnome wallpaper themes)
[Discover] KDE and Gnome Comparison http://www.psychocats.net/ubuntu/kdegnome (ubuntu kde gnome comparison)
[Discover] Switch Between Gnome And KDE Desktops In Ubuntu Or Kubuntu http://www.watchingthenet.com/switch-between-gnome-and-kde-desktops-in-ubuntu-or-kubuntu.html (kde linux ubuntu gnome)
[Discover] Ubuntu Installation - Beagle http://www.beaglewiki.org/index.php/UbuntuInstall (search beagle linux gnome)
[Discover] GNOME-Look.org http://www.gnome-look.org/ (linux gnome wallpaper themes)
[Discover] KDE and Gnome Comparison http://www.psychocats.net/ubuntu/kdegnome (ubuntu kde gnome comparison)
[Discover] Switch Between Gnome And KDE Desktops In Ubuntu Or Kubuntu http://www.watchingthenet.com/switch-between-gnome-and-kde-desktops-in-ubuntu-or-kubuntu.html (kde linux ubuntu gnome)
[Discover] Ubuntu Installation - Beagle http://www.beaglewiki.org/index.php/UbuntuInstall (search beagle linux gnome)