I got ethereal to work fairly easily.
First, install Apple's X11 (very easy).
Then, install Fink (very easy).
Then install Fink Commander (very easy).
Then use Fink Commander to get ethereal (so-so easy).
Then, once fink has installed ethereal, just open X11 from the Utilites folder. A terminal window will appear. In that window, type sudo /sw/bin/ethereal . It should launch. (If you don't run it as root/sudo, it won't see an Airport card.)
Then get someone to show you ethereal if you're not already familiar with it.
tooki