From an iPhone?? Through iTunes? This is my firstmAndroid device
I had enough trouble getting a ring tone onto my wife's iPhone from her old Android phone. I can probably try to do it the other way around, but I'd rather not waste another 4 hours of my life and endless frustration.
If you are intrested in trying, I would suggest you try to find the .m4r file for that ringtone. If you manage to find it, rename it so the extension is .m4a. Then you have to find some program to convert .m4a files to .wav or .mp3 format. Then copy the file onto your Android phone. This is more or less the reverse of what I had to go through in addition to changing some import config settings in iTunes.