If you own the copyright for the items you would be distributing, then yes, there is no problem, you can do what you want with them.
Make sure you let people know what they are allowed to do with them.
If you do not own the copyright, then you need the owner's permission to re-distribute the files. For Ring Tones, you can obtain a licence to sell them from the Performing Rights Society, though the cost may be prohibitive. Have a look at their
web site under the ringtones section.