Pretty much everyone I know in the music industry started out as an intern.
If you're not born into it, you gotta work/grind for it. Music Business school is helpful, but it seems that you can get more experience, as much networking and spend less dinero interning.
I myself started interning at a booking agency during college and in my first week I dropped a $250,000.00 check for a not-so-great Canadian band behind the copy machine. I spent 20 minutes leaning on the copy machine...learning names, acting cool, a lot of pointing at people walking by and poking behind the copy machine with my feet.
I found it.