This is an ALTERNATE version of the installation. If you want gnome easily, simply find it in the software center. This method may supply you with a newer version of gnome, however.
This is a very simple guide for new users.
Gnome is a desktop preferred by some over the default unity.
Here is how to install it on Ubuntu 12.04/12.10/13.04!
Note: the reccomendations section is incomplete, if you have any good gnome addons please add them!
Ubuntu 13.04-Get set up with Gnome
Copyright (C) 2013 will1982. License: CC-BY-SA http://creativecommons.org/licenses/by-sa/3.0/
Revision 1, Aug 6 2013
Written for Ubuntu 12.04, 12.10, and 13.04
First, open up a terminal window. In it, type, on different lines:
sudo add-apt-repository ppa:gnome3-team/gnome3
sudo apt-get update
sudo apt-get install gnome-shell
Reboot your computer.
Now, on the login screen, click the little Ubuntu logo. Change it to "Gnome". Proceed to login.
You now have a working gnome desktop! The rest of this guide is optional, but may help to enhance your experience.
You can download extensions from the gnome website (https://extensions.gnome.org/).
Here are some I reccomend:
Frippery: a more "classic" gnome experience. Combines the best of GNOME 2 and GNOME 3.