I've used e-bay a time or two. $19.95 does sound excessive for shipping - especially since it's a small, light weight item. You have to look at it like this - is the item worth $40 to you? If it is, then it's a good deal.
You can also read the feedback that the seller has gotten. This particular seller has 100% feedback which is a good sign. Definately read all the feedback. You can (and should) ask questions before bidding AND if you don't like what you get when you get it - try to return it for a refund. You can always post a complaint with e-bay.
Not a bad way to shop, you just have to be cautious and don't expect too much.
Good luck!