http://snapshot.debian.org/package/fglrx-driver/1%3A11-6-3/
Caution: Debian and Ubuntu are disimilar enough that packages may not install properly because of the way each builds their packages.
Usage
In order to browse snapshots of the archives kept on snapshot.debian.org, simply follow the links on the top left. They will lead you to a list of months for which data was imported, and the list entries in turn will point you to all timestamps of a given month's snapshots.
For example, /archive/debian/ shows that we have imports for the main Debian archive, http://ftp.debian.org/debian/, from 2005 until the present. Picking October of 2009, /archive/debian/?year=2009;month=10, provides us with a list of many different states of the debian archive, roughly spaced 6 hours apart (the update frequency of ftp.debian.org at that time). Following any of these links, say /archive/debian/20091004T111800Z/, shows how ftp.debian.org/debian looked on the 4th of October 2009 at around 11:18 UTC.
If you want to add a specific date's archive to your apt sources.list simply add an entry like these:
deb http://snapshot.debian.org/archive/debian/20091004T111800Z/ lenny main
deb-src http://snapshot.debian.org/archive/debian/20091004T111800Z/ lenny main
deb http://snapshot.debian.org/archive/debian-security/20091004T121501Z/ lenny/updates main
deb-src http://snapshot.debian.org/archive/debian-security/20091004T121501Z/ lenny/updates main
To learn which snapshots exist, i.e. which date strings are valid, simply browse the list as mentioned above. Valid date formats are yyyymmddThhmmssZ or simply yyyymmdd. If there is no import at the exact time you specified you will get the latest available timestamp which is before the time you specified.
It may be necessary to ignore the Valid-Until header within Release files, in order to prevent apt from disregarding snapshot entries ("Release file expired"). Use aptitude -o Acquire::Check-Valid-Until=false update or apt-get -o Acquire::Check-Valid-Until=false update for this purpose.
Reproduced from here: http://snapshot.debian.org
This is what I added to my sources.list:
11-6-3 Seen in debian on 2011-07-20 03:31:11 in /pool/non-free/f/fglrx-driver.
Below is an example based on the above line you would put into your /etc/apt/sources.list
#After your done installing, comment them out until you need them again.
deb http://snapshot.debian.org/archive/debian/20110720/ lenny main non-free
deb-src http://snapshot.debian.org/archive/debian/20110720/ lenny main non-free
deb http://snapshot.debian.org/archive/debian-security/20110720/ lenny/updates main non-free
deb-src http://snapshot.debian.org/archive/debian-security/20110720/ lenny/updates main non-free
Note: I have tried this out and couldn't get it to work. Got depends errors for XOrg saying it needs 7.6....as well as other fglrx packages. I tried the above with only the above sources active, disabling all of the other sources. I tried with Lubuntu 11.04 64 bit installed to a hard drive. I also tried installing just the binary's but they get similar results about Xorg needing newer 7.6.