Superman #219 and Action Comics #829 have sold out, according to dccomics.com.
These are the first two parts of the 4 part Sacrifice series.
4-part “Sacrifice,” arcing through all the Superman books and WONDER WOMAN #219 and featuring the return of Superman’s deadliest enemies! Brainiac knows all of the Man of Steel’s secrets, and he’s putting that knowledge to use in a lethal fashion. Is Superman about to lose another piece of his humanity?