Rice Chex - the new one from General Mills is totally gluten free it says on the front of the package now. (in the last month!!! hurrah!!!) Now, Strawberry, Corn and Honey Chex are GF! IF they say on the label!
I know that there are several others that are gluten free, but don't label it yet. Trix? Cocoa Pebbles (I think) Fruity pebbles, Dora the Explorer cereal. (I know you have always wanted to eat Dora the Explorer cereal!)
We don't eat sugared cereals as much at our house, so I don't know for certain, but what you are looking to avoid on the label is malt extract ( from barley) and oatmeal aside from the regular listings of wheat products.
At the health food store, there are gluten free cereals everywhere. Expensive, five bucks or so.
Health Valley Corn and Rice CrunchEms is good for a Chex fix and Mesa Sunrise is a good sub for Wheaties. There is a brown rice krisp by Erewhon cereal that substitutes for Rice Krispies too.
These are just a few we have discovered.