Moto KRZR ringtones?

I want to do my own ringtones for my Moto KRZR phone but I just can't. So far I know they have to be MIDI files for the phone to recognize them, but i haven't found any good programs to make my mp3's into midi files. Also I've heard MIDI files are simpler and do not allow humans voices like MP3 files?
Where can I find free software to do the conversion?

All Verizon phones support MP3 ringtones. You just have to make sure they are no more than :30 in length.
I suggest you use MP3 ringtones instead of MIDI ringtones. MIDI sucks.
For the ringtones, either use mobile17.com or go buy a rintone software kit from wal-mart. They have to be 30 seconds or less for the phone to accept them as ringtones.

Thanks for the help! I want to put the ringtone of the spider on my Moto KRZR.