Many people have been posting they are looking for a good sleeve for their 11" MacBook Air. Price is $15-$20 and maker can offer variations on fabric designs by request. Great feedback on Ebay and long time MacRumors members. Been using one for my 13" with great success but the majority have been for 11". PM if interested.
Link to picture: http://gallery.me.com/psparaco#100538&view=grid&bgcolor=black&sel=0
Link to picture: http://gallery.me.com/psparaco#100538&view=grid&bgcolor=black&sel=0