Not my tutorials, but Audacity's. I had reason to use the splitting up a large file tutorial recently.

The recorder orchestra I play in did a "spot" at the (UK) national recorder festival and I recorded the performance, which meant setting up a mic and my Edirol R09, pressing record and running back to my seat to play. The resulting large file of a concerto in three movements had then to be split into separate tracks, one for each movement. The Audacity tutorial proved very easy to follow and it worked very well.

If you are interested, you can hear the result here The piece in question is the Steve Marshall Recorder Concerto. Before anyone makes remarks about the amount of reverb, the performance was in a School Gym, so you can imagine what the room acoustics were like [grin]