Setting up wifi on a Debian IRLP node is fairly easy to do.
First, you will want to install wireless-tools and the wpasupplicant
COMMAND: apt-get install wireless-tools wpasupplicant
Then have a look at
You need to manually edit your /etc/network/interfaces file to do it, and that is the hardest part.
Some good info about systems that require boot-time firmware is available at:
Dave Cameron VE7LTD