The Duke University Master in Management Studies is ideally suited for someone without a business undergrad, but also allows business undergrads to enhance their knowledge and experience while studying for another year. The program has been improving every year with better and better placements. A friend of mine is at the program currently and has nothing but positive things to say about it.
Duke has a blog set up run by students that provides an insight into what the day to day is like in the MMS program. They also have a Tumblr account which is helpful. I am including links to both below.
Here is a link to the Duke Master in Management Studies Program