Multi-track recording software all work on a basic principle: stacking audio and then tweaking each individual track so it's just loud or soft enough, contains the desired effects (like reverb), and when played back outputs a cohesive final mix.
I've created a short video tutorial on how to record and edit with Audacity which I have placed at my personal website, radioEARTH. You can view it online.
I've also created "Learn To Edit Audio Like A Radio Pro". This is a free 4-day online editing course that will teach you how to edit like a Radio professional.