I'm *not* an expert by any means, I've only been baking seriously for about 1 1/2 years. I'm still a bit "shy" about playing with additives and such.
My hard wheat comes in "feed bags" which are some sort of plastic. My soft wheat comes in paper of the sort paper bags are made from. I store both in 5 gallon plastic buckets with a plastic top... it's tight enough that it's rodent-proof. I picked some of these up at Walmart.
People going for longer-term storage than I am do much more complex stuff involving dried ice in gas-impermeable plastic bags to limit the oxygen exposure, but unground wheat keeps for a long time, so I don't see the point really. The fat in whole wheat flour goes rancid over time if it's sitting around ground, but unground stuff lasts for years.
Some people do freeze it and that apparently works fine. I think you need to thaw it before grinding though.
I only clean the outside of the grain mill. I believe that the stones and such inside are not supposed to get wet. I basically just discard a bit of flour when I first start working it to "clean" the inside. I also keep it covered except when in use so nothing drops into there (also for rodent control as you never have all the grains out* of the thing).
My emphasis on rodent-proof is because we live pretty rurally on a small farm and in spite of 2 cats, I have some mice problems. Most of you probably won't as I sure as heck didn't before I moved to the country. My one cat caught 2-3 mice daily all summer long and doesn't seem to have dented the local population any. Blech.
Anyways, the grinder is too much of a pain to get in and out every time I use it as it's very, very heavy. So I picked up a single kitchen cabinet countertop at an auction for a buck and my husband bolted the grinder on it. If you look up reviews of grinders, this one is one of the easiest to use... which is largely why I bought it. Even so, once my husband attached a bicycle to it so I could grind by foot instead of by hand, it was a great relief. It's more work than you think grinding grain, especially if you're out-of-shape. The whole thing, gridner on cabinet with bike attached to the grinder with a belt, sits on my covered porch next to my freezer.
It takes about 15 minutes to grind enough wheat for the recipe I gave above if you leave out the oats and use all wheat (around 8-10 cups).
They sell a motorization kit if you don't want to hand-grind. I'm planning to live without electricty in a few years which is why we just went with the homemade cabinet/bike contraption.
Buying wheat online costs too much as the shipping for 50 lbs of wheat costs more than 50 lbs wheat itself does as wheat is incredibly cheap. So you're best finding a local source.
If you have any Amish or Mennonites in your community, I hear they run really cheap bulk groceries, but I haven't found any around here though I'm in PA, guess I don't know the right people.
Also, there's no food co-ops in my area, which would be another good source if you have one locally.
I'm currently buying hard wheat at a local mill. It is really cheap, around $5 for 50 lb, which makes an insane amount of bread.
Hard wheat is what you want for yeast-based breads as soft wheat doesn't have enough gluten. Hard wheat grinds into the equivalent of whole wheat bread flour (I assume you guys know about the different flours given that this is a bread newsgroup).
I also use hard wheat for noodles and pasta as I don't buy durum wheat specifically and it works fine for that.
Soft wheat is for baking-powder type recipes: quick breads, pancakes, biscuits, etc. It basically grinds into the equivalent of whole wheat pastry flour.
I was cooking with whole wheat before we started grinding our own and grinding made a *big* difference. Whole wheat panacakes were *always* disgusting until I had fresh-ground wheat. I even do stuff like cookies and cakes and such with whole wheat and it works fine.
And the bread made from freshly-ground wheat is just *awesome*.
On the other hand, I haven't yet gotten a good biscuit out of whole wheat flour, whether fresh ground or not, but still have a bunch more recipes to experiment with, so have not given up yet!
I completly ignore the distinctions beween red and white wheat and/or spring versus winter wheat - I just pay attention to the hard vs. soft bit cause I understand what gluten does. Because I buy in bulk, I haven't bought often enough to have opinions on the other distinctions yet.
No one around here had any clue about soft wheat (mills and other bulk grain type places), so I asked a local health food store to order me some in bulk. The health food store was a bit weirded out by me not wanting *organic* wheat, but went ahead and ordered it for me anyways (they drew the line at ordering bulk white sugar though!) It costs a bit more than the hard wheat as it's not a local source really even though it's a locally-run store (not a franchise).
I was very surprised to discover even though I bake all our bread, turns out we use much more soft wheat than hard wheat.