Take a look at how I setup my ath0 configuration. I have a feeling you could adapt it to your system pretty easily, unless someone gives you an answer that's "right" for your card and OS. It's the second post in this thread. You can probably ignore the first two steps.
http://www.linuxquestions.org/questi....php?p=2537921
Everything happens out of the interfaces file, so you don't have the problem of having a script that doesn't run until after the networking is all setup. Anyway, just change the file names, interface names, wireless setup, etc, to match yours. I'll try to answer any customization questions you have.
ADDED:
On looking at this again, I'm not happy with your needing to run "/sbin/insmod rt73.ko". Do you have an /etc/modules file? If so, you should be able to add a line containing simply "rt73". But that should have been taken care of when you installed the driver. Assuming that you compiled the driver you downloaded, did you run "make install"? That's all I needed when I installed madwifi to get my ath0 module loaded during boot. The scripts I put together in that link above are just to setup the connection to my router and then run dhcp.
