Ah, the most common question asked by weekend hackers - How do I spin the ball?
The problem is, spin is highly overrated. You don't necessarily need or should want spin, you want your ball to land softly.
If you don't know how to do it you're going to get yourself in trouble. The WORST thing you can do is open up your face and try to spin it with a fade or a slice swing. Though this will give you immediate results, you will kill your game in the long run.
The best way to stop your approach shots is to open up the face, play the ball back in your swing and abbreviate your finish. A slight, emphasis on slight, fade is also a very easy way to control your ball flight and land soft.
But back to the question - how does one spin a ball? First of all, you have to use a really soft ball. I've been playing the Titleist Pro V1, but any balata, wound, or surlyn ball will do just fine. Play the ball back in your stance. Now, here's the part that separates the pros from mere mortals. You have to hit the ball absolutely pure. You don't hit the ground first, you don't need to change your swing -- you need to clip the ball with a downward blow and clip it perfectly. That is why even pros can't spin the ball from in close or in the rough - you can't put the spin velocity on the ball necessary to bite.
What technically happens is that the club strikes the ball with a normal downward blow so cleanly that the friction spins the ball with tremendous velocity. You will see a large divot because the player strikes down completely through the ball, not scooping like most players do.
I personally hate more than 5 inches of spin and used to work hard to eliminate it from my game. I will overclub and swing slower to eliminate it if I'm in position. In the past 10 years, the only course I TRIED to spin the ball significantly was Pinehurst #2 because the crown on those greens was insane.
To be frank, you're not going to be able to spin the ball like you see on tv and you will only harm your game trying. Work on playing the ball further back in your stance, opening up your toe and taking your normal swing with an abbreviated follow-throuh. Take the ball in high and soft and you will love the results.
I'll be happy to share my golf knowledge with anyone if they have questions -- at least I can provide something to this board