Ambrosia Software has released iToner which enables you to quickly transfer custom ringtones for your iPhone – without modifying, hacking or having to reset your iPhone.
Simply drag and drop your MP3 or AAC audio files on iToner’s window, click the Sync button, and you’re done!
Even better, your ringtones will continue to work with future iPhone OS updates.
Your iPhone allows you to assign different ringtones for your different contacts. With iToner, now you can have a Barry White ringtone for when your girlfriend calls, Frank Zappa for when your college buddies ring you up, or the theme from Jaws for when your boss is calling.
iToner 1.0 costs US$15 and features a free fully-functional trial works for 30-days.
More info and download link (here.
Tested – works like a charm. Wonder if this works with stuff from Universal Music Group? 
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