Creating ringtones on Windows Phone isn't technically a difficult task, but it's not incredibly straight forward either. Nokia has taken steps to address this for its Lumia Windows Phone owners with a new app that's available in the Nokia Collection. Ringtone Maker is a simple app that does exactly what it says on the tin - it enables users to take tracks saved locally on the device and turn them into ringtones.
This eliminates the requirement to upload, edit and save files which is what's necessary to create ringtones in Windows Phone. The only problem with Nokia's ringtone app is that it doesn't appear to support tracks downloaded through Xbox Music (songs downloaded for offline usage, as well as purchased tracks) which is a shame. We attempted to purchase a track from the Store but it still didn't show up when using Ringtone Maker.
The reviews for the app have been negative thus far, so we can only assume problems we've experienced are hitting other users. This is a bummer as we'd expect Nokia to completely test apps before releasing them to the Windows Phone Store. So Ringtone Maker is a superb solution, should you be able to get it to work. There are other Ringtone Maker apps available too.