networking - How do I install my wireless card driver offline

I just installed Xubunu 13.04, but it didn't detect my wireless card.
This is my wireless card:

Broadcom Corporation:BCM4312 802.11b/g LP-PHY: Wireless 1397 WLAN Mini-Card

I googled about it, and I found this solution :

Once you have confirmed that your WLAN device is supported, you may
proceed to installing the driver by running the following command from
Terminal window.

sudo apt-get install firmware-b43-installer

The problem is that I can't run this command in a terminal because I've no connection in xubntu. I'm currently posting this thread from Windows.

I downloaded the package firmware-b43-installer from debian, and when I tried to install it, it told me that I need the b43-fwcutter package so I download it, and when I tried to install it the terminal shows me that the installation needs some sources from the internet.

I don't have an Ethernet or some other internet connection source, the only way I can access to internet is from Windows.

How can I install my wireless card driver offline ?

I have done it on Xubuntu 12.10 (Quantal Quetzal):

1. Download firmware-b43-installer and b43-fwcutter from Ubuntu, choose the target release version (I chose Quantal) and architecture.

   
   
   
   
   
   
   • Alternatively, if you have a Live CD or installed *Ubuntu of the same release with Internet access, you can do: apt-get -d install firmware-b43-installer and then look for both packages in /var/cache/apt/archives. Do not use packages from different releases.
   
   
   • Do not download from Debian. Being a derivative does not imply that they are compatible, and does not imply that Debian's packages are suitable for Ubuntu.
   
   



2. On the target machine, do dpkg -i b43-fwcutter* && dpkg -i firmware-b43-installer*

   
   
   
   
   
   • b43-fwcutter is a dependency of firmware-b43-installer, so it must be installed first.