I use coconut (online through tropical traditions)and blanched almond (online through honeyville farm). If you do not have Celiac, then other good ones to use is buckwheat, oat and brown rice. Try to buy organic.
Also….if you want to follow a gluten free diet, Elana’s pantry and Gluten free Goddess websites. Our family is on gluten free, due to having a daughter with Celiac so have done lots of research on who to follow.