As far as I know thats not possible. I just got a bluetooth adapter for my computer and it sends ringtones, pics, videos, etc to the phone really easily.
I don't know if it counts for the RAZR, but on the KRAZR you can send an email from any email account to your phone (10digit phone #)@vtext.com. Just put the file in as the attachment and it comes through. You can then save the file as a ringtone. This may cost you money depending on your plan.