Debian :: Installing ATI Radeon HD 5700 Driver On Squeeze 6.0.1

I've been on numerous websites--with tutorials telling how to install the ATI drivers, I'm running Squeeze 6.0.1 Gnome amd64, the tutorial I am using is located at the ATIProprietary Debian Wiki [URL] when I try the following:
sudo apt-get install fakeroot debhelper build-essential libstdc++5

I get this:
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package fakeroot is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or is only available from another source.

Package debhelper is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source
E: Package 'fakeroot' has no installation candidate
E: Package 'debhelper' has no installation candidate
E: Unable to locate package build-essentials
E: Unable to locate package libstdc++5
E: Couldn't find any package by regex 'libstdc++5'

I have a feeling that apt-get is not searching the web, yet searching a CD perhaps? Because when I've tried the apt-get update, I get the following:
Ign cdrom://[Debian GNU/Linux 6.0.0 _Squeeze_ - Official Snapshot amd64 LIVE/INSTALL Binary 20110324-08:54] squeeze Release.gpg
Media change: please insert the disc labeled
'Debian GNU/Linux 6.0.0 _Squeeze_ - Official Snapshot amd64 LIVE/INSTALL Binary 20110324-08:54'
in the drive '/media/cdrom/' and press enter

After doing that, nothing happens, and my apt-get still doesn't work, everything I try and install like build-essential says it's not found. Also when I
su
nano /ect/apt/sources.lst
the list in nano is empty???

I'm currently running a dual boot with windows xp/debian but as soon as I can get everything working, I'm going to turn this into a full linux system. Also my sound doesn't work, but my sound is HD sound that goes via the video card, I have it hooked up HDMI to my LG tv/monitor, sound works fine on xp. I think once I get the video card drivers installed it should possibly fix my sound issues at the same time.