The Windows Mobile 6 SDK Refresh is available today. It includes some documentation enhancements and new samples. One of these is called RingtoneManager and is a C# application which wraps all the Sound APIs for ringtone management and sound playback, the latter of which were introduced with Windows Mobile 6. This is great because it gives you all the P/Invokes etc you need to use this functionality yourself. However expect to see these Windows Mobile specific APIs in the next version of Mobile In The Hand.