I would recomend following the guide here
The guide tells you to add a ppa as this driver does not appear to have the best version in the kernel or something.
sudo add-apt-repository ppa:mpodroid/mactel
sudo apt-get update
sudo apt-get install b43-fwcutter firmware-b43-instal
After you have installed these you need to install the linux-backports-modules-cw-3.2-oneiric-generic via
sudo apt-get install linux-backports-modules-cw-3.2-oneiric-generic
Unless, if you have the pae kernel installed (you would know if you do), the linux-backports-modules-cw-3.2-oneiric-generic-pae package. (as the guide says)
sudo apt-get install linux-backports-modules-cw-3.2-oneiric-generic-pae
Next you should edit a couple files
gksudo gedit /etc/modprobe.d/blacklist.conf
Once that is open add the line
next edit one more file with
make sure the wireless modules (b43 and bcma) are blacklisted (takin from guide)
After you install the drivers as discribed in the steps above and edit some files,you can reboot by rebooting your normal way, or simply keeping your terminal session open and typing:
Again, this is all taken from the guide I linked in the first sentence, so if this does not make sense, feel free to look there as well.