Sing and Change the Transpose/Pitch

Okay, Imagine this. Plug in a microphone to the Digitone. Play all four tracks. Set one of the tracks so that the pitch transposes given the measure of the tone of your good or bad singing voice. Any ideas on how this can be done, if this can be done at all? Cheers.

Merry Christmas, would love to know how to transpose a track given the pitch change in plugged-in microphone. Any ideas?