HT4623: Update your iPhone, iPad, or iPod touchLearn about Update your iPhone, iPad, or iPod touch
Currently Being ModeratedJan 18, 2013 7:22 PM (in response to siong23)
At the present time, redownloading purchased ringtones is not supported if that's what you're trying to do. You can check your purchase history as outlined here: http://support.apple.com/kb/HT2727, but you can't redownload a purchased ringtone.
Currently Being ModeratedSep 26, 2013 11:28 AM (in response to siong23)
I called Apple Care and they told me the only way to restore is buying them back again. Ridiculous, specialy if you are buying a new iPhone and you have to shell money again for your ringtones. They are not back up in iCloud or local backup.