You don't have a TractorSupply store or Southern Agriculture store, or Atwoods around anywhere? I made the mistake of buying stuff online only to find out that it is much, much cheaper to goto your local feed/cattle type store, even if you have to drive a little. If you don't then maybe you can goto where I bought my first batch of stuff, it's free shipping, but like I said, check around what might be local to your location.
Here is what I use and have had great results. Start with the red bag, then when they're older goto the green bag, then when ready to start laying eggs goto the blue bag and brown bag is scratch grain to supplement when they're closer to being and/or already are adult birds.
We usually pick things up at local farm stores, feed stores and feed mills. Otherwise, you usually end up spending more, with the price of the item and the shipping. Online, most of the larger hatcheries have brooding supplies and other chicken supplies, if you want to comparison shop. Just google chicken hatchery. I usually only shop online if it's something I can't find locally. Looking around locally will also give you a chance to look for a local source for feed. Shipping on 50lb bags of feed is really expensive.
Here is a coupon to get the purina cheaper. I don't work for purina, I promise, lol, and I'm sure there are lots of other good feeds out there. I would recommend getting a "starter" type that is "medicated" for the newbies and once again, try your best to find supplies that are close to where you live. There isn't any reason spending 1000% (seriously, do the math!!!) more than you have to for chicken feed. You'll go thru it quicker than you think. I would also avoid buying the watering and feeding devices that are sold in the stores or online. Go into the BYC feeder/waterer section and build your own, with PVC pipe and use poultry nipples, they will stay a whole lot cleaner, less food/water waste, and hassle free and your chickens will love poop free food and water, plus they'll stay healthy.
I would only buy the things I could not get locally even if the online store has it cheaper. It would have to be significantly cheaper for me to do it. You have to factor in the cost of the item the tax and the shipping. Plus the whole instant gratification thingy....LOL.
Good local sources for some supplies are Home Depot, Lowes, even Walmart.
Any Feed store will have supplies such as feeders and waterers nest boxes, heat lamp bulbs for chicks, regular light bulbs are getting hard to find. They will also have first aid supplies for livestock and wormers and mite dust.
Amazon is a good source for reference material like books. As a matter of fact Amazon has had some very good prices on those things I couldn't find elsewhere. Often times Amazon is the place where online stores sell their lost leader items. A lost leader in retail is something brought in to sell at cost or at a loss to bring in customers. Since online stores dont have a place for people to come in to they use Amazon to provide a link to their own website. So I follow the links on Amazon and have found some really great suppliers of things I cant find locally.