I don't know your husband but I would get something revolving around his hobbies or activities or his fantasies. If he's a movie or sports buff, a lovely little movie or sports package including tickets or gift cards to attend an event. Does he like jewelry or watches? Does he need a case to keep them in. Perhaps a keepsake photo album of your favorite moments of the last 11 years with memorable comments or sayings in them.
His favorite meal.
11 idex cards with why you love and respect him which you read to him out loud in front of a group of family or guests.
Keep it simple but focused on him and your relationship and the things the two of you could enjoy together.