Samsung handset is a garbage

Very disappointed as its not abe to make own mp3 song as a ringer tune. I talked to some mobile tech they say it's not even possible to flash or debrand it....but in other Nokia,Erricson possible. They even told stay way this garbage brand if u r into ringtune things. However my first set was samsung used in Asia was nice but this NorthAmercan cariers made samsung a garbage.