Combine bones with remaining ingredients in a large (5-6qt) slow cooker. Start on high for 1-2 hours, then low for 8-10 hours. Allow some cooling time, but do not let stock go to room temperature.
Strain & Store
Put a colander into a very large bowl (best done in a sink) and pour in stock. Lift out colander, and discard contents. Strain what's left in the bowl with a fine mesh strainer into smaller, freezable containers.
Notes
You can add other veggie scraps too. I wouldn't recommend using it right away. After freezing, or refrigerating, a layer of fat will form on top that can be removed and discarded to make it a bit healthier. Then again...