how do i join several short tracks to make one big one?

Answer 1

This is what you need:

Audacity - http://audacity.sourceforge.net/

You could splice several track into one using that free software!

Answer 2

use an udio editor like the wave editor in Nero, or some other audio editing program....all you do is select to "add file" and place the cursor where you want the "next piece" to go in the track.