I don't really do too much substitution to be honest, I just monitor what I eat pretty carefully. One of the biggest misnomers I have come across in dealing with other people and diabetes, is that they get shocked if they see me eat something that traditionally would be a "no-no".
If my friend has a birthday, I am going to eat a piece of cake, a small piece, but a piece nonetheless.In college I avoided the ramen-noodle diet fairly well, but new out of college, I am a volunteer with a religious organization, and my roommates and I only get $75 a week to feed three people, which is sometimes really difficult. Avoiding things like pasta and rice is hard, because they are staple items for simple living, and cheap. I combat that by eating vegetables as much as possible and limited my intake of those carbs. I do exercise fairly regularly, and I am coach for the track and field team so what carbs I do eat are worked off.