I found the essential oil at our local health food store. If you have something like a Whole Foods or Central Market near you, they'd have it too. You can also order it online, although paying for shipping is a bummer.
It is called essential oil. It's different than say, flavoring extract you'd use to cook with from the grocery store. You can get all kinds of essential oils, in nearly any flower/plant/fruit/tree scent you can think of.
The oil and food coloring is sort of added to your taste, depending on whether you want a really intense color and smell, or something more subtle. Basically just a few drops of each.
All you have to do is screw the lids on the jars, you don't have to seal them as if you were canning food.
Hope that helps. Let me know if you think of anything else.
