You're new at recording, producing is a whole different ballgame... ;)

Anyway, there's a ton of different software out there for multi-track recording, here's a few:

- Cakewalk
- Sonar
- Logic Audio
- Cubase
- ProTools (you might want to check out the free version)
- CoolEdit Pro (now called "Adobe Audition")
- N-tracks

Along with that you'll need a soundcard too, unless you want to try things out first with the one built into your PC.

Your friend is right, you could plug the guitar into a DI box, straight into the mic input of your soundcard, and manipulate your sound using plug-ins...
OR, you could plug your guitar into an amp simulating processor, and plug that into the line in of your soundcard.
OR, put a mic in front of your guitar amp, and plug that mic into your soundcard.

So, there's many options...