In Chapter 9, Bella experiences a flashback when she begins to piece together the facts:  Edward's strength, speed, and cool skin.  She remembers the Quileute legends and tells Edward that she knows he is a vampire.

In Chapter 6, Sam tells Bella that the Cullens don't come here, referring to the Quileute reservation.  This provides an allusion that there is more to know about the relationship between the Quileute people and the Cullen Family.

An example of dramatic irony occurs in Chapter 5, when Bella faints in Biology class during blood-typing.  The nurse assumed that she fainted at the sight of blood, but Bella inisted that it was the smell of blood that makes Bella faint, even though humans are not supposed to smell blood.

An example of verbal irony is given in Chapter 9 when the Cullen family refers to themselves as vegetarians, because they survive by drinking the blood of animals instead of people.

An example of situational irony also involves food and can be found in Chapter 1 ... at the moment Bella first sees the Cullen family.  The Cullen family sits in the cafeteria and pretend to eat human food, even though they are surrounded their natural food (the other human students).

Source:

Meyer, Stephenie. Twilight. Atom Books, 2009.