foreign websites like mrtone, ringtones.com, theringtonefactory.com offer downloadable ringtones but not applicable to some countries like the Philippines.......except ringingphone.com which offers limited tones.
why not create your own nalang para gamit yung software na kasama ng phones? for the 6600, just use an mp3, the crop the particular part of the song you want and save it. then upload it using the pc suite bundled with the phone.