All of us in the IBS community have different bodies, different digestive systems, and different mindsets. So although I agree with most of the IBS diet, I have taken the liberty to eat organic yogurt and organic cheese, mostly because I was tired of eating soy cheese and I can't stand soy yogurt!
For yogurt I eat Stonyfield Farms, they have lots of variety, as well as frozen yogurt, and all include a healthy dose of probiotics. I do eat non-fat and low-fat yogurt and frozen yogurt. And for cheeses I stick to hard cheese with low lactose such as parmesan, cheddar, swiss.
I know that many people do not think eating dairy is safe, but I say just try a little at a time and see what happens. You never know until you try! As for milk, I drink almond milk and it is wonderful.