Our program put us in touch so we could arrange that. I have been told that many classmates share apartments, at least in the first year. It is a common thing.
I will share an apartment with one classmate. We got in touch through email and decided some basic principles, on which we agreed, and started looking some stuff on the web.
I guess it could work or not... But I preferred not to be alone! I know I won't be talking about economics the whole day, I am not that kind of person. But, if you have to choose someones, I think it is better is he is in your program. That way, in the first year, your schedules will much and will save a lot of problems (unless he or you could be very lazy).
One thing I think you should keep in mind is culture. We all have different backgrounds and sometimes we are used to very different arranges regarding food, hygiene, etc. It is highly likely that you you could have better chemistry with roomies from some places.
I will tell you how things works lately!