Golf Swing Fan: Increase Golf Swing Speed
To increase golf swing speed, you must train your golf specific muscles to fire at a faster rate, but still under control to keep the ball in play and not cost you strokes. An excellent training aid for this is the Power Golf Swing Fan. This swing trainer has 4 fins on it so when you swing it, you get resistance from the air via the fins.
Ping G20 Hybrid


What I like most about these golf swing trainers is it's a real club that you make golf swings with, so it's very golf specific. Strengthening AND stretching the muscles involved in increasing clubhead and golf swing speed.
Ping G20 Irons


You will NOT increase swing speed by pounding more balls. It's not going to happen. You need to add resistance to your muscles to strengthen them, and for them to move at a faster rate of speed.