For an essay on whether or not Oedipus knows himself, how can I find textual evidence about how hie doesn't know himself, specifically when he finds out he is the son of the woman he married?

Certainly Oedipus does not know himself at the beginning of the play, and the play really turns on the moment when he learns the awful truth. One fascinating quote from the play reveals the inner thoughts of the title character as he first begins to suspect his origins. As Jocasta reveals that King Laius was "murdered on a day by highwaymen . . . at a spot where three roads meet," and that his son was left to die as an infant to avoid prophecy, Oedipus begins to suspect the worst. He exclaims to his wife (who he does not yet know is his mother):

What memories, what wild tumult of the soul Came o'er me, lady, as I heard thee speak!

At this moment, Oedipus recognizes his past experience in Jocasta's narration of her husband's death, and he is, of course, horrified by the truth. At this moment he learns who he really is, and that it is his behavior that has brought the horrible curse down upon the city of Thebes.
http://classics.mit.edu/Sophocles/oedipus.html