How do I get custom ringtone off my iPhone and into iTunes

I recently reformatted my laptop and now I need to get my ringtones off my iphone and into itunes so I can back them up but when i check sync tones, iTunes is telling me it will erase all tones on my iPhone 4 and replace with tones on current iTunes library (and there are no tones on current iTunes library.) Is there a way to save my ringtones that Ive created that are only on my iPhone?