Why-oh-why, is she aware that you'd really like some clean surfaces in the house?
The first thing you have to do is talk to her and tell HER how you feel.
If she's able to think and reason, she's able to make changes. I, too, wonder if she knows how much this bothers you.
I wonder if you can come up with a compromise, certain places where you have a "surface area" to yourself that she is not allowed to place any of her own items. Tell her this is making you insane and you need it for your own sanity...
I wonder if she has always been like this, or if it is recent behavior? If you haven't always known her like this, I would be very concerned that her cluttering is going to get worse.