In the novel there is a main part about Johnny Fontane and his wifes and problems etc. Not in the film.
There is also a part in the novel were Bonasera is in court which is not in the film.
Also there is a part were Nazorine realizes that he has to go to Don Corleone to make sure Enzo can stay in America.


Don Michael Corleone: "My father is no different than any other powerful man."