Yep. Assuming you have already created your ringtone (less than 1MB and 39 sec max - WMA or MP3), right click on your ringtone in Zune and select Edit. Change the Genre to RINGTONE (use caps, don't know why). The first one you will have to type out the word. After that select off the dropdown list. Click OK and drag your ringtone down to the sync icon. That's it.
I have been using Sound Editor in Roxio Creator 9 to make my ringtones. I also remove all artist, title info about the song so that all my ringtones appear within Zune as Unknown Artist. Easier to keep them organized.
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