I would guess any ornamental grass which is no taller than 2' will grow fine in 11" of the right kind of soil. They may or may not require periodic root pruning, because as they mature, they may become rootbound, but you'd likely need to divide them periodically anyway.

Spend some time looking at the comparison chart here:

http://www.bluestem.ca/grass-comparison-chart.htm

You can browse by size, habit, color, zone, etc..and each listing has links to photos and more information.