Recommendations...

[Susan Cragin]

I haven't gotten wireless to work yet but I haven't spent time on it beyond trying the default Ubuntu stuff.

>If you have a Broadcom chip, just install /b43/-/fwcutter/ from the
>Ubuntu repos. During installation it pops up a dialog whether you want
>to download the firmware or not. Just click yes, and your wireless will
>come right up. Most Intel wireless chips work out of the box.

Or try System/Administration/Hardware Drivers.
Install the wireless drivers that way, and re-boot. 

I install wicd-gtk and wicd before I start, but that's because I also use fluxbox in addition to gnome.