How do I stop a monthly charge of $5.04 from APL*ITUNES I don't want?
As it is a monthly charge and the same charge every month it is probably a subscription

To view and cancel your subscriptions on a Mac:


  
  Open iTunes on your Mac.
  Go to the Store section of your Music library.
  Click on the Accounts link in the right column.
  Sign in, if necessary
  Scroll down to the Settings header and click  Manage next to
  Subscriptions.
  


(source)