In Adim X-tras!
a style called Modified Seph Status Bubbles says
TO INSTALL:
1. Right-click Adium and choose "Show Package contents"
2. Navigate to Contents/Resources/Status Icons/Gems.AdiumStatusIcons/
3. Copy all files from the zip and paste them into the folder you just navigated to (click yes to replace them, if it asks you).
4. Restart Adium.
...so double clicking the app doesn't work (as that just launches it) but Ctrl-clicking the app does get me to package contents.
Having said that I did replace the files but restarting Adium didn't get the contact style skin working. I haven't tried to figure out what I am doing wrong yet.... having a bad computer day and moved on to more pressing issues!

"The only real difference between the Sane and the Insane, in this world, is the Sane have the power to have the Insane locked up. That is the bottom line. CLANG!" Hunter S. Thompson