Local LFS gets comet goldfish feeders for $ 7 per 100.
I made friends with some of the LFS owners. One gets the feeders for me at that price and another gets a pound of black worms for me for $ 16.
In the Summer, live feeders around here are free. You may catch them by the hundreds in 30 minutes using bait traps. You get festae, tilapia, jewel, and PB fries.
For bulk buys try www.aquaticeco.com or Florida Tropical Fish Farm Association's coop store. You do not have to be a member nor a fish farmer to buy from them.
Ken's fish and brineshrimpdirect have some of the lowest prices for fish food on the net.