I got my interview by calling them. I had gotten an invite from Ohio State, and since I'm flying from CA, I called them and asked if I might go there while I was in the area. They were very accomodating.
What's bugging me, though, is that the lady there said I was supposed to be getting some sort of packet in the mail regarding the interview. This was the middle of last week. As of yesterday's mail, nothing. I think if if doesn't come today I'll call tomorrow. Anyone know what's in the packet besides the invite letter?