I am assuming that you have a pc and not a MAc for this and that you have a reasonable spec by todays standards re RAM, CPU speed etc.
First off you need a good soundcard - you can get by with a creative labs card that comes built into most pc's but for agood music production you will need something more powerful.
You will also need a DAW application for recording, mixing, sequencing, editing and mastering. For this you can download Reaper for free - it's excellent and can do pretty much anything. Get it here:http://www.reaper.fm/download.php
After that, it depends on how you want to record your guitars, you can either mic them up or go direct via USB (digital) or analgue to a reamp (built into some high end soundcards). The standard good quality entry level instrument mic is the Sure SM57 - however, there is a lot to be said for going direct (via PODxt, Digitech GNX series or Boss GT series etc), especially when you are starting out.
Vocals obviously go in via a mic - lots of choice there depending on your budget.
Lots more to mention.... way too much for this post. Hope this answers some of your questions.