Hi! I'm a recent grad who actually graduated from the OSU critical care nursing internship back in November, so I understand what you are going through with the application process. The OSU internship is very competitive and I know my program manager said she was hiring fewer nurses this time d/t the shortage of jobs (OSU Medical Center has a <1% vacancy rate right now).
I can tell you from my experience that I applied for the internship in Oct. and was interviewed and hired the first week of January '06. The main reason I was offered an interview was that I called and followed up when I didn't hear back from the manager. So, I would strongly encourage you to call and find out if you can interview.
Besides the OSU internship, though, I know the Mt. Carmel and Ohio Health hospital systems in Columbus offer internships in different specialties - I was just talking with a girl about that today at work. So, don't be discouraged - check out your other options. I don't know of any job fairs at this point, but if I see ads for them around the hospital I can send you a message here via the website. Good luck - Columbus has lots of nurses, unfortunately for us new grads.