My essay topic is about superstition in the book Julius Caesar...I need some help finding the title for it.?

Use part of one of the prophecies as a title. "Beware the Ides of March" is almost overused, but "A Lioness Whelped In the Street: Supernatural Warnings in Julius Caesar" would be good. It's known but not as commonly used. Incidentally, you might want to refer to Julius Caesar as a play rather than a book in your thesis statement.