Listen to the Nikon D3000 shutter sound
Almost as pleasant as the sound of the birds singing is the sound of the shutter clicking. And the sound of the Nikon D300 shutter is what you will find in the DC Watch preview of the camera. There are plenty of pictures of the camera-body, and towards the bottom of the page, you will find two mp3 files with the shutter sounds. Ring-tone anyone? :)
There are no samples taken with the camera, but they have plenty of pictures of the camera body itself.