Ubuntu 8.10 is very old now, so I would strongly suggest getting the 9.10 release, out yesterday (at time of writing)
this is massively updated from 8.10 and should have your wireless devices drivers in the kernel.
If you DON'T want to upgrade, there is something called Ndiswrapper, which will use windoze drivers in linux, which i have done in the past and it works great.
sudo apt-get install ndiswrpper-common ndisgtk
in the terminal
then go to System > Administration > Windows Wireless Drivers
and click the add button
you need to find the .inf and .sys files from your wireless install CD. if you dont have it anymore, you can sometimes extract the files from a downloaded .exe installer, and get them that way.
After you've found the files, browse to them in Ndisgtk (Windows Wireless Drivers) and find the .inf, and open it. Ndisgtk will do the rest and, if all is well, you should be able to reboot and connect.
This should do it