Zelev - I'm right there with you. Some of my references are even older and I need to contact them too. Don't you just hate how schools want actual letters or forms filled out for references? It's so much simpler to just give names, addresses and phone numbers.

I would contact them by email and definitely tell them about the interview. In addition, your master teachers and supervisors may have some contacts that are useful to you. I wouldn't worry about the break in communication too much. Remember that master teachers and supervisors are used to having to give references - it's part of their job, so you shouldn't feel bad about asking for the references. Good luck!