Is all oatmeal gluten-free?
There's a lot of controversy around oats and gluten -- apparently, there is a risk of cross-contamination with wheat in many/most of the factories that produce oatmeal. If you have a serious gluten allergy, you may want to steer clear of oatmeal, or at least do some more research on the subject. Here's a good site: www.celiac.com
No, because of the cross-contamination issue Merrill mentioned. I use Bob's Red Mill Gluten Free Rolled Oats when cooking for my father, who has celiac disease. There may be other brands (I haven't looked) but this one is well-tolerated by my father.
Gifts of Nature also has gluten-free oats:
I've only ever seen Bob's Red Mill and Gifts of Nature selling gluten-free oats, so look carefully at any other brand for a note about gluten-free. Otherwise, the oats are likely grown on the same land and processed on the same equipment as regular oats, so they're open to cross-contamination. Oat flour is subject to the same problem.
Trader Joe's also sells new Gluten free rolled oats in a bag, and it might be a little cheaper than Bobs Red Mill.
It's also important to remember, that along with cross-contamination, some celiacs just can't eat oats. Depending on their level of sensitivity, not all GF-eaters can deal with oats.