Unscented mice are mice that AREN'T SCENTED. Wow.
To scent a mouse, you rub another prey item on it, whatever that may be, a fish, frog, snake, etc. And that is called SCENTING.
T.T. - A $10 garter snake is not something anybody should want. If it was that low in price, it's obviously WC or a CB that is not eating or deformed in some way. There is no such thing as a red ringneck snake. A $15 feeder snake is barely worth buying, in my opinion. My friend that buys corn snakes for feeders, buys them at $9 each, in large quantities so there are discounts.
It's easier to observe snakes in captivity, than in the wild.
Mike
http://www.freewebs.com/mikesnake