newbielink:http://www.playbill.com/features/article/98021.html [nonactive]
found this article recently, so feel free to read. But otherwise..
PSM roles pretty much vary from my understanding, depending on who you're working for. If you're PSMing a National Tour, it is definitely different than working for any one theatre NY/LA bound or not. I guess the PSM pretty much becomes the director once a show starts, as the director no longer comes to shows. He manages the production... and all the questions or changes that may go occur or need to be made. All the departments of the show feed to him, with as well as his SM's and ASM's. I'd check out the internet to see if you can get in touch to talk with one... I met The PSM of a broadway tour last week,and shadowing/talking with him helped very much with understanding his job. If you can't find it anywhere online, I'd say go shadow one.. the experience will help you understand the job having been able to see it done rather than just reading of the job. Hope this helps..