<<Disclaimer: Verify this information before applying it to your situation.>>

I have found a Health Food store in my city, who now has a web page w/
mail order.  They categorize their different food products.  Gluten-free
is one of their categories.  Among the cold cereals listed were
Barbara's Corn Flakes as well as Barbara's other cereals.  I emailed
them and told them these were not gluten free.  Her quick response was
they would update their catalog as soon as they could.  They have  a
nice variety of things listed, and are quite helpful.  You might want to
check it out.
The web page is a www.akins.com .
Kris