Motorola ROKR E1
mp3 as ringtone
Just drag and drop the file into the phone (it shows up as a mass storage device in XP) instead of loading it from iTunes. You should be able to access it from the "sounds" menu then and set it as a ringtone. A song from iTunes cannot be used as a ringtone....only entertainment.
You would have to have Mobile Phone Tools which is a cd rom that allows you to sync the phone to your computer... Then you have to move the mp3's onto the phone flash card like a drag drop USB would...