How do I stop Apple from offering me iTunes 11 as a software download in OS X I don't want to disable Apple software update, I just want to prevent myself from accidentally overwriting my iTunes 10 with a working Party Shuffle/iTunes DJ with the new iTunes 11. I have iTunes 11 at work, where it doesn't really matter what I've got installed because I can't play music during the day, and I've tried to come up with some combination of smart playlists that effectively duplicates iTunes DJ... but it doesn't work. The tools aren't there.

So, how do I do it, how do I selectively block updates for iTunes 11?

Edit/Update: All the helpful answers here are no longer useful.

Don't do it. Later versions of OSX ship with a newer iTunes and rolling back to iTunes 10 breaks some aspects of Software Update. I ended up having to reinstall and use Migration Assistant to restore from Time Machine to get a fully working system again.

Update: With Catalina they replaced iTunes with Music which is a whole new ball of problems. This question does not apply to Music.
The methods differ based on whether you are using OS X Mountain Lion, or an earlier edition.

For OS X Mountain Lion (where updates are now merged with the Mac App Store):


Refer to HT2357 How can you ignore a software update in Mountain Lion? &ndash; Apple Support Communities. Quoting the accepted solution from DickVH: 



  For the software update you would like to hide - make sure the full
  description of the update is shown - click "More..." if needed to show
  the full description
  
  Right click on the update window.  Select "Hide update"
  
  This will hide the update and it will not show in the App Store
  Updates Window or counted on the dock icon. [...]
  
  [emphasis above is mine]


For OS X Lion and earlier:


Refer to OS X: How to ignore a Software Update &ndash; Apple Support. Quote:



  How to ignore an update
    [Mac OS X 10.3, Mac OS X 10.4, Mac OS X 10.5, Mac OS X 10.6, OS X Lion]
  
  
  Choose Software Update from the Apple menu.
  Click Show Details when prompted.
  Click to select the name of the update you wish to ignore.
  Choose Ignore Update… from the Update menu. A confirmation dialog appears that states, "Are you sure you want to
  remove the update (name of update) from the list? You will no longer
  be notified of new versions of this update. To see this update again,
  choose Software Update > Reset Ignored Updates."
  Click OK.