From a recent emergency prep/food storage class in my ward:
Essentials you must store to make bread:
GRINDER
An electric one is best, but it's good to have a hand grinder as well, in case the power goes out. However, a hand grinder is a LOT of work for a little flour, so for everyday use, get an electric one if you can.
WHEAT
Hard Red and Hard White wheat store best. It can be stored for 30+ years if kept below 74 degrees. Use wheat with at least 12% protein and less than 12% moisture. The higher protein content forms enough gluten to make the bread rise well and the low moisture content helps to prevent growth of fungi and bacteria during storage. Red wheat is acidic and white wheat is alkaline, so white wheat is, for some people, easier on the digestive system. Wheat stored at high temperatures -- in a garage or shed during summer heat -- will not make bread that rises well, but in an emergency you can eat bread that is not "beautiful".
Protein content varies depending on the grower. If you have lower-protein wheat you can experiment with adding gluten flour or dough enhancer (like lemon juice, Vitamin C powder, vinegar or a commercial dough enhancer) to your bread dough.
You can also make bread from white flour, although it doesn't have the fiber of whole wheat. Storage life of white flour is 10+ years if kept under 74 degrees. Freshly ground whole wheat flour will go rancid quickly, so store it in the fridge until you use it, or in the freezer if you need to store it longer than about a week.
YEAST
Yeast will store up to 7 years if frozen in the freezer. A good quality yeast should be in a foil packet with all the oxygen removed. This makes a "brick-like" package. A year's supply for one person is about 1-2 lbs.
Active Dry Yeast is usually dissolved in warm water with sweetener.
Instant Yeast can be added directly to the bread without first dissolving it in water. It raises in half the time of regular yeast. It is a much more aggressive yeast. Note: Some people are finding that instant yeast is linked to candida health issues and allergies. This may not be a problem for everyone, but you can experiment and see what works for your family.
OIL
Any oil will work. You can experiment to see what your family likes. Oil doesn't have a very long storage life, but baking bread is a great way to rotate oil. Oil stores approximately 1 year.
SWEETENER
Sweetener is needed to activate the yeast. A lot of bread recipes call for honey. This has a nice flavor. Sugar can also be used. Both will store indefinitely.
SALT
8 lbs of salt is recommended per person for a year. Approximately 1-2 tablespoons of salt are used in a bread recipe, depending on the size of the batch.
Optional Items:
GLUTEN FLOUR
This can help wheat bread rise higher. If unopened, gluten flour lasts approximately five years. Once it is opened it lasts two years.
DOUGH ENHANCER
This gives bread a fine, light texture and preserves moistness. Commercial dough enhancer has a shelf life of about 3 years.
BREAD MIXER
Bread can be made entirely by hand, but a mixer will make it easier. A large mixer with a dough hook will work, and most can make 4-6 loaves at a time. A breadmaker is a fast, convenient way to make one loaf at a time.