Try
www.vetamerica.com. They have dry cat food as well as canned. Enter SAVE5 at checkout to save 5$ on an order over 59$. Their prices didn't look bad at all, example 4 lb C/D dry feline was 15.99. That sounds horrendous, I know, but I was paying a lot more at the vet. Shipping is a flat rate of 5.50 per order.
I now buy the big bags and store the food in Tupperware cereal storers to keep them fresh.
Hope this helps!