My hair is stick straight and I still have wild frizzies all the time. Especially now that I'm getting older. It's weird but I suppose it may be losing pigment (which I can't see because I color it) so it's getting more and more dry. I only wash my hair every 3 days but I do tend to wet it and put conditioner in while I'm soaping in the shower and rinse it out just before getting out of the shower. I haven't found a single product that doesn't make my hair look greasy to keep the frizzies away. My hair is also fine so most products just weigh it down.
The goth store sounds like it may be good and if they don't carry it, chances are someone who works there or anyone who shops there will know where to purchase it.