i have a sprint lg cell phone,i had a rington put into it when i first got it

[whizzer 360.]

over a year ago,its getting? on my nerves now and id like to change it but i cannot get rid of this obnoxious ringtone! i tried everything even my brother tried it and he knows more about this sort of thing than i do,what and how can i get this ringtone off my phone?