My aunt has a severe case of Crohn's and has had most of her intestine removed. She highly recommends the book
Breaking the Vicious Cycle by Elaine Gottschall. About two years ago they told her that she had precancerous cells on what was left of her intestine and that she was going to have to have surgery again. She started the diet and within 6 months those pre-cancerous cells were gone and she was able to go off most of her meds (which she'd been on for about 20 years).
I don't have Crohn's but I've read the book and follow a similar diet. I highly recommend checking it out if you have Crohn's, Celiac's, Autism, IBS or Colitis.