hmmm, the problem with ordering bulk foods online is the shipping. when i was living back East, i fell in love with www.nutsonline.com because they have a huge selection, good prices, and amazing customer service. but now that i'm back in California, the cost of shipping from their NJ warehouse kills me.
i may check out one of these sites next, since they're based in CO:
or this one, because it looks like they offer $5 super-saver shipping if you spend a certain amount:
you can occasionally find really good deals on Amazon.
but you honestly may just be better off joining a local co-op if you have one nearby.