I think what I want to do is simple- but i can not figure it out. I store my music library on an external drive. Works fine when tethered via thunderbolt- but when I go remote I off course lose access. So- I want to keep part of my iTunes library on the internal local drive of my macbook pro. I also want the ability to make changes to the local media- adding and removing songs at will. Is there a way to organize iTunes to see and recognize a media file regardless of location? In other words- when I'm connected to the external I see and have access to everything. And then when I'm remote- iTunes will only show me the files on the local drive?