Hiya oldiebutgoodie! :)
You can get it jsut about anywhere. So long as it's pure it's fine. You'll pay more at a health food store but it won't necessarily be better enough to warrant the price. The last bottle I bought was a large bottle from a little Middle-Eastern grocery store - at least, it was owned/operated by Middle-Easterners, but it had Twinkies too. ;) It only cost me a couple bucks so of course I jumped on it.
The catalogue I reference further down this page has it and additives
to it too I think, for scent, herbal properties, the like.