First, you need to install wireless tools:
#apt-get install wireless-tools
Second, I have never gotten an Atheros wifi card working with ndiswrapper, but others have. Atheros is supported by madwifi:
http://sourceforge.net/projects/madwifi/
Look at that website. Also, look in the hcl on this forum for your wireless card and see what others have written about it. I finally got my card working by following instructions I got from someone from the hcl.
Good luck!