Don't know if this product is available elsewhere or not.
Simply Organic Peppermint Flavored Oil is available at Freddy's and at Kroger. It's really a mix of Peppermint Oil and Sunflower Oil, so it's pretty high calorie, but for flavoring, it doesn't take much at all. Two drops to 24 oz of water and ice, makes for a great drink that you'll spend more calories drinking than get from the drink.
In addition to that, it's great for helping with asthma.