Samsung MM-A920 (SPH-920)
To get ringtones or other media (video and MP3′s) from your PC to your mobile phone, you need a data card reader (SD reader). Unfortunately I can’t find any software that will currently enable you to load ringtones from your PC to your Samsung A920 via a data cable.
You need to make a folder on the SD card called ‘media‘ and load the mp3′s there. Works fine as my research have indicated.