Personally, I order a lot online. I can find most things at the local Whole Foods (organic shoyo, sea veggies, japanese noodles), but even they don't carry hulled barley, whole oats, umeboshi vinegar, bancha tea, etc.

We have several Japanese groceries here, but they don't carry all natural items and it's easy to accidently buy something full of crap. They do have the best selection of udon and soba noodles, though.

Try Goldmine (http://www.goldminenaturalfoods.com) or Simply Natural (http://www.simply-natural.biz)