cant find a command line.
Then open a terminal (it'll be in your menus somewhere) or Alt-F2 and run xterm
That's where you type commands.
network controller: Broadcom BCM4309 802.11a/b/g (rev 3)
That should work with the bcm43xx module.
Is it loaded? Find out with
lsmod | grep bcm
If it is not listed, load it:
sudo modprobe bcm43xx
Now see if your chipset is detected:
You should see your wireless interface listed.
[Edit:] also, please see here: http://linuxwireless.org/en/users/Drivers/b43
because it looks as though b43xx has been replaced by b43