ATT may have taken the... opportunity to upgrade you to their new plan style. Hopefully the call will be easier than you expect, but I wonder if they counted the iPhone plan as different than a normal plan. They did with Blackberry. Anyway.
You should get a file manager on your phone, but you can setup folders using your computer as well if you connect your HOX as a drive. Download Astro File manager (there are many available) and you can browse the phone's file system just like on a computer. You can do the same by plugging into a PC and selecting DISK DRIVE instead of CHARGE ONLY. If you meant the folders you can create on your phone's home screens, simply drop one icon on top of another, and a folder is created.
The easiest way I can think of to get your music over, is to use Google Play Music.
https://forums.androidcentral.com/e...//play.google.com/music/listen&token=tRsDGUVY
You can upload music from iTunes to Play, and can do whatever you want to with it from there... best thing of course is stream it to your phone using the Play Music app. But you can access from any web browser, so you can play it at work easily too. Pretty slick. If you have more music than free space The Goog gives you, you can choose to pay for more of course... but there is an app that pulls from itunes to your PC, so you can copy as you like to your phone from there. I forget the name offhand, but someone should chime in.
Good luck and welcome aboard.