ringtone (noun): the sound a phone makes when it receives an incoming call
Artist: Jonathan Taylor Brittunculi
iPhone supports M4R only. Download to your computer and add to iTunes. Then sync to your iPhone.
For phones other than iPhone, you can typically visit this page on your phone and download direct to your phone.
Samsung supports AAC and MP3.
For other phones, please check your userguide. Most phones support a variety of the above formats.