Easiest, best chicken stock in the world: Buy a non-funky chicken (organic or grain-fed), roll it in salt, (after removing the innards, of course) plunk it in a roasting pan with garlic, new potatoes, beets, and turnips, or whatever root vegetable-like things you have. Roast on 450 until chicken is to temperature and skin is crispy and potatoes are soft. Eat.
Take the leftover carcass and bits (not the innards, but I guess you could use them. I always give mine to the dog.) and place them in the slow cooker. Fit to top with water, turn on high for about two hours, then on low overnight. I don't bother trying to clean the meat off the bones; it all goes in, often along with leftover garlic or wine, sometimes the vegetables too.
You will awake to sweet-smelling stock. This is where a not-funky chicken makes a huge difference. If you use factory chicken, the house stinks all night. I've even been woken up by the stench.
Running it through a colander. Allow the stock to have fat, bits of chicken or flavorings and density. Cool, and pour into baggies for the freezer. Lasts for ages; instantly usable.