I'm running Ubuntu 8.10, and was unable to connect wirelessly from HP G60-235DX. I tried a number of things (can't remember them all), but here's what I tried that worked.
I'm a complete newbie, so I tried everything in the first link. The first section didn't work so I tried a second. Finally, when I rebooted I was given an option to view the wireless connections.
I could not stay connected and so I tried everything in the second link.
I see a lot of people having wifi issues w/ Ubuntu, and if you haven't already, check your router configurations. Some laptops don't like mac addressing, for instance. I'm not sure of all the technical terms but you may have to play around with your encryption settings, and possibly make it a little less secure (at least initially) to get a good connection.
I found the above links here : http://ubuntuforums.org/showthread.php?t=1025417
I was finally able to find something that worked by adding the model of my computer to my google searches.