depends.. if you have the latest iTunes then you can only make the music that you buy off iTunes into ring tones... they have to be the ones that iTunes says it is ok for you to do that... there is a little bell next to the song
You have to have openSSH installed on the phone, a WiFI connection, and for WinSCP you need windows but there is also a program for Mac.
But fist you have to find your phones IP which you can get in the WiFI menu under settings. Then you open WinSCP or mac equivalent, then you but the IP address where it says host name, leave the port as 22, user name is root PW is dottie, where it says file protocol select SCP, then hit login.
Now you have access to the directories in your iPhone.
I found the ringtones at var/root/Library/Ringtones.