That's in Breaking Dawn.
The first time Edward says i love you directly to Bella is in Twilight page 319
nice question, the firts time is pg.85 in Breaking Dawn
In order for Twilight * Page 274 (Edward says it) * Page 314 (Bella says it) * Page 366 (Edward says it in many words) * Page 418 (Edward and Bella) * Page 456 (Edward says it) * Page 479 (Edward and Bella) * Page 498 (Bella says it)
edward and Bella's graduation begins on page 352 in eclipse. i am on page 355!
edward first says hello to Bella on page 43
about page 80
Edward tells Bella that she is his life now in "Twilight" on page 221.
It's not in there since it is from Bella's POV but one can assume she told him sometime during the days that Alice was staying with Bella
Page 43.
Edward Cullen says "You are my life now" to Bella Swan in the movie "Twilight" during a scene where he reveals his true identity as a vampire to her. He expresses his love and devotion to her in this moment.
Edward leaves Bella in New Moon chapter 3, page 60. =)
It starts on page 48