Solved my own problem. Just follow the instructions below if you have similar issues.
Using Ubuntu-supplied fglrx/Catalyst
On Ubuntu Quantal, this will install fglrx/Catalyst 9.000, which is roughly equivalent to Catalyst 12-9. NOTE: You must have the restricted repository enabled in Applications -> Software Sources... for this to work. After you complete the install, skip to Generate a new /etc/X11/xorg.conf file.
Command line
sudo apt-get install linux-source fglrx fglrx-amdcccle
GUI
Jockey was removed in 12.10. You now need to go to Software Sources and go to the Additional Hardware tab. You will need to install linux-headers-generic beforehand, or the Panel won't show up after the restart.
Installing Catalyst Manually (from AMD/ATI's site)
I recommend copying and pasting the commands to ensure there are no typing mistakes and speed up the install process. Remember to use Ctrl + Shift + V or Shift + Insert to paste into the terminal (or go to the terminals menu, select edit and click paste).
Before you start
If you have previously attempted installing Catalyst, remove any leftover files by following the Removing the Driver section. Make sure universe and multiverse are enabled in your repository sources (System -> Administration -> Software Sources). or Applications->Ubuntu Software Center->Edit->Software sources->Other software: check canonical partners.
Install the prerequisite packages:
sudo apt-get install build-essential cdbs dh-make dkms execstack dh-modaliases linux-headers-generic fakeroot
If you are using the x86_64 architecture (64 bit):
sudo apt-get install lib32gcc1
Create a directory for the build environment and move to that directory
mkdir catalyst13.4 && cd catalyst13.4
Download the latest Catalyst package.
This package contains both the 32-bit and 64-bit driver.
wget http://www2.ati.com/drivers/linux/amd-catalyst-13.4-linux-x86.x86_64.zip
unzip amd-catalyst-13.4-linux-x86.x86_64.zip
chmod +x amd-catalyst-13.4-linux-x86.x86_64.run
Create and install .deb packages.
sudo ./amd-catalyst-13.4-linux-x86.x86_64.run --buildpkg Ubuntu/quantal
sudo dpkg -i fglrx*.deb
Test your installation
NOTE: if you don't reboot first, fglrxinfo gives an error message. Reboot the computer and type
fglrxinfo
into the terminal. If the vendor string contains ATI, you have installed the driver successfully. Using fglrxinfo on a system with Catalyst 12-3 and a RadeonHD 4550 returns:
display: :0.0 screen: 0
OpenGL vendor string: ATI Technologies Inc.
OpenGL renderer string: ATI Radeon HD 4550 (This line may be different depending on what graphics card you are using.)
OpenGL version string: 3.3.11566 Compatibility Profile Context (This line may be different depending on what graphics card and
Catalyst version you are using.)
Now, try:
fgl_glxgears
If you experience issues or a hang, you may need to disable fast TLS.
sudo amdconfig --tls=0