Ever wondered what those 2 tiny plastic nodules are, on the F and J keys on your PC keyboard? Apparently, they're for use by people who can type properly. Without looking at the keys. F and J are known as the "home keys". With your 2 index fingers correctly positioned on those keys, everything else should come naturally as you work towards being a touch-typist.
If you don't fancy spending money on a copy of Mavis Beacon, or another software package, you could do worse than pointing your web browser at www.typingweb.com. There's a series of exercises to help you hone your typing skills.
The site is free, and you get useful stats to help you judge your progress. It's a little heavy on the adverts, but at least they don't intrude into the exercises themselves.