Going to Mountain Home? It doesn't get really cold there (below -40°), I don't think, at least not very often.
Don't worry. Use your choice of 5W-30 or 0W-30 oil. Synthetic lube in a manual transmission is a really good idea, or just shift at the speed the lever will move--don't try to rush it. It's also good for differentials and automatics, but not as important. Remember, most folks use the lubes from the auto factory. Any good standard battery is OK; a large capacity battery is better if you need a new one. 50-50 antifreeze/water should be OK, or maybe use 60% antifreeze / 40% distilled water.
An engine block water jacket heater is good but not essential. They heat the coolant for easier starting, more even engine temperatures while it's warming, give better gas mileage 'cuz your engine's computer controls don't need to keep the fuel mixture extra rich for so long, lower emissions for this same reason, and best of all the heater comes on sooner. There are electric oil pan heaters and battery heaters, also, but I don't think you'll need those until you go to Elmendorf.
Do get four good winter tires..."All Season" tires truthfully are three season. Do get winter wiper blades with the rubber boot over the metal parts. Do get a couple of good windshield scrapers and brushes, and carry warm gloves. Whe it gets below -20°, be ready to scrape the frost off the inside of your windows. Oh, yeah, find an empty snowy paved lot and practice winter driving...braking, sharp fast turns, recovering from skids, etc.
Ken