Ok firstly... Poke root!! That's such a great name!

Anywho, immaturity aside, I've also heard it's good for mastitis - 2-4 drops in water in the morning for a couple of days apparently (though I'd look into it a bit more before taking it!). As for where to get it, I'd say a health food shop would be your best bet, and if they don't have it they could usually tell you where to get it.