MidiEditor is a MIDI creation program that allows you make your own MIDI ringtones.

RingtoneEditor lets you edit your existing MP3 ringtones to your exact liking. You can import your newly created MP3 ringtones or select a CD track and select the exact location and length of the final ringtone before uploading to your phone. You can select and play as you edit so that you get the exact ringtone you want to have. You can even change the bit rate of the selection to have better file size control.

Select from a large assortment of instruments, build your new MIDI ringtone, save it and then upload it direct to your cell phone. You can even add any number of tracks to give you a more sterophonic sound and the most unique MIDI ringtone ever.