Right now Amazon.com has Bob's Red Mill Brown Rice Flour at a GREAT price!
If you use the subscribe & save function you can get 12lbs (!) of Brown rice flour for only $16.76 shipped!
That works out to $1.39 per pound. Thats a better price than I can find locally.
I am not sure how long it will be at this price, so make sure you double check before purchasing.