Uninstall itunes and install the old version
iTunes 10,7 download
You will also need to recover the backup library made when you updated.
you can get 11 to look much like 10
ALT shows the menu bar temporarily
CTRL+B show/hide menu bar
CTRL+S show/hide side bar
CTRL+/ show/hide status bar
To make search more like it was, click on magnifying glass in search bar and uncheck "search entire library"
You can also make a smart play list that works much like iTunes DJ
Here is an example I have for general pop music