This application will capture sounds, perform an FFT and plot it to a graph. This should help with the tutorial, but it is also a great tool if you want to analyze sounds for some reason. Maybe you want to study the harmonics of a guitar string or piano, or the non-periodic sound that emanates from a drum.
The Sound Analyzer requires Flash 10 or above and a microphone, so hopefully a microphone is built into your computer, or you have one handy! If Flash recognizes your microphone, it will ask you for permission to use it, and you would select "allow" to get it to work with the application.
There are instructions on how to use the Sound Analyzer. Check out the menu of the application.
Try it out!