If you live around Marysville, Ohio (43040) try JB's Pet Corral, 937-644-1600. They have a lot of QUALITY bird food products, and what they don't have, they can probably order for you.
The following online Bird Supply stores are wonderful - I've ordered from most of them:
(Please note - these are not links, just the names of the sites. And they are in alphabetical order, just to make them easier for me to list -they are not in order of preference.)
Many of the below online stores will run specials from time to time, so if you are looking for a specific product, it doesn't hurt to shop around a little to compare prices - and be sure to include shipping in the comparisons. If a price seems too good to be true, contact the company and make sure they are not selling expired items (seed, supplements, etc.)
If you can, purchase items in bulk that don't expire (cuttlebone, charcoal, nesting material, etc.), it can save you a ton of money.
abbaseed.com (finch seed, proso [white] millet, mineralized oyster shell)
birdsupplynh.com (plastic canary nests with extenders, ground oyster shell, fine charcoal, breeding aid, sisal & coco fiber nesting material)
bovinedoc1 (username on ebay, 1cc needleless syringes)
cuttleboneplus.com (cuttlebones & fine oyster shell)
Demsondinc (username on ebay, for travel cages, breeding cages & racks)
drsfostersmith.com (proso [white] millet)
finchniche.com (flexible plastic crop feeding syringes, travel cages)
foyspigeonsupplies.com (handfeeding formula, breeding aid)
globalpigeon.com (global pigeon supplies)
L&M Bird Leg Bands, Inc.
ladygouldianfinch.com (KD water cleanser)
realsalt.com (a few sprinkles of their Kosher mineralized sea salt is wonderful in birds' grit bowl)
revivalanimal.com (1cc syringes)
theeggshop.com (looks like they have very nice dummy eggs)