From the people I've known to do it, I guess you just contact a hospital directly and ask them. Logically, it would help to call a place where you know other people have done it. The only places (two of them, one in Brooklyn, one in New Jersey) where I saw people as externs had externs from India. I don't know about any places that had Filipino folks. It's not that it matters, but it could help you.
That's my minimal information. Sorry I can't help more.