Right, here are some links and info if you hadn't found them already-

The driver installation file:
support.amd.com/.../index.aspx>
of course, this is ATI proprietary, so you are downloading a 120 MB
".run" file, of which the first several hundred lines are human
readable. The rest is the usual "blob". So I am using the term
"script" a bit loosely. :)

Installation help specific to Ubuntu are here:
https://help.ubuntu.com/community/BinaryDriverHowto/ATI>

For the manual installation, you need to modify the tail-end of your
build command. Instead of Ubuntu/oneric as in the example, that
command will need to end in Ubuntu/lucid.

One additional note for you:

Quoting from that page above: "The easiest way to install binary
drivers is to use the built in Hardware Drivers manager in Ubuntu. In
Ubuntu 10.10, this is found under System -> Administration ->
Additional Drivers." So worth it also to check that first. My system
does not have that option since it is the 10.04 server base. Checking
the repository didn't show the package even available, but I'll keep
my fingers crossed for you, as that sounds super easy.