Having a hard time finding shadowing opportunities

Lately I have been having a very hard time finding shadowing opportunities. I've cold called and emailed (literally) hundreds of offices and clinics only to get the cold shoulder every single time. I've no idea what kind of physician I actually want to be and have targeted numerous specialties (ranging from family practice to neurosurgery) in the hopes that I will get a response.

I'm in a BS/MD program and in addition to the GPA and MCAT requirements (like all BS/MD programs), we need 50 hours of shadowing by the end of each academic year. I've been fortunate enough to have one surgeon (an ophthalmologist) who has been kind enough to let me shadow him for a decent amount of time, but every time I have tried to branch out into different medical and surgical subspecialties...nothing. Even the contacts this particular ophthalmologist has provided me yield only radio silence.

I am at my wit's end. What can I do? It seems like trying to find a physician to shadow in the Long Island, New York area is next to impossible. :\