I make a lot of phone calls! Some feeds are cheaper than others. I am a huge Purina fan however it also happens to be one of the more expensive feeds. I get it at Nolands feed in Casper, they are the cheapest Purina dealer. The only problem is that Purina only sells a medicated meat bird feed. Nutrina has a non medicated meat bird feed, if you want to go all natural. I plan on using this for my meat flock since I'm trying to produce my naturally. I have not priced it yet. Star line feed in Mills has Ranch Way feed for even cheaper than the others. I debating using it, however I've never had as good results with Ranch Way with my horses as I have Purina, so I'm still on the fence there. Ranch Way also produces a Certified organic feed however its EXPENSIVE so I haven't priced it locally or even checked to see if it is available. Sutherlands home improvement in Casper also sells Ranch Way feeds. Avoid any feed store in Douglas, they are WAY too expensive, I have not checked hardware hank in Douglas though, they sell nutrina.
Check out the fermented feed thread also. I noticed that once I started feeding fermented feed as a snack their unfermented feed consumption has decreased but the birds are happier and healthier.
I hope this helps.