Newbie help. - Sending a ringtone throught a text message - motorola T720 - T731c

I apologize if this is an easy answer, but I could not fine it on the web or
throught google groups.

I can find ringtones on the net, although it does take some time. But
instead of typing them on my phone I would like to copy and paste it to a
text message that I could send to myself, which works except that I cannot
get the email program on the phone to store it in the composer. Is there
some header I must put on the text message to have it identified as a
ringtone?

Any thoughts?

TIA,
Randy