1) can i sync with itunes?
2) if not, how do i put new music on my iphone
3) if needed, how do i un-jailbreak my phone?
4) how do i put files (such as roms) from my computer to my iphone?
5) how do i create a folder on my iphone for files and what do i name that folder?
6) is it possible to transfer files via usb from computer to iphone?
thanks in advance for help and answers to these questions
1. Yes you can sync with itunes at any time.
2.You can also use other applications to sync music ex. winamp
3. To un-jailbreak just use itunes to restore your phone back to its original state.
4. To transfer roms you can use SSH. Google for instructions.
5. SSH
6. There are apps that allow you you to transfer files via usb, also you can use wifi and SSH to transfer files.