Wedges

Wedges are my most important clubs.  Being accurate with your wedges is an easy way to knock strokes off.  If I am within 125 yards of the hole, I'm almost guaranteed to be within 3 strokes of finishing.  To be good with your wedges, though, you need good wedges.

Most iron sets come with a pitching wedge and a sand wedge.  The pitching wedge is usually perfectly adequate.  It matches the weight and feel of your other irons, so you'll be comfortable with it.  Also, the distance will be consistent with your other irons, so it will be more predictable.  The sand wedge, however, is usually not great.

I would invest the $75-$150 in a Cleveland sand wedge.  They are so perfectly weighted and durable that it becomes hard to hit a poor shot.  As long as you keep the grooves clean, you can control spin from the sand better.  I'd estimate that a good sand wedge can knock off 4-5 strokes per round for the average hack.

Once you have the club, though, the trick is learning to use it.  Practice practice practice!  When I'm playing by myself, I usually play 2 or 3 balls from each spot.  I treat solo rounds like the pros treat a practice round.  Just use it to try things.  During these rounds is where you hit 4 or 5 balls out of the sand.  Try pressing the ball in with your foot, or finding damp and hard sand to hit from.

Also, most people find that they hit their sand wedge around 60-75 yards for a 56 degree sand wedge with a full swing.  Nobody ever does though.  Try hitting your sand wedge with a full swing at the driving range.  Remember to keep the club more upright than you would in the sand, since it can't sink into the ground like it would the sand.  Also, make a steeper downswing.  If you hit the ball clean, it's virtually impossible not to get some backspin, which will impress your friends.