The Internet provides a goldmine of online video instruction. The following videos have been collected from various sources, and linked here to give a comprehensive golf training instruction set.

Practising golf does not always mean 'on the golf course'. These drills will help correct any body and swing faults, and can be done anywhere you can swing a club.

Set Up Drills

These drills will help you set up the ball and the target, before you even attempt to swing.

Ball Position Setup - setup your ball position properly
Correct Tee Height - correct technique for teeing up your ball.
Aim and Alignment - setup your aim and alignment properly.
Ball Flight Path To Target Line - use "back to square" drill to drive the golf ball down the target line.

Back Swing Drills

Common problems with the back swing are sliding of the hips, over-rotation of the hips and incorrect swing plane. Practice these drills to correct any problems you have in this area.

Backswing Variations - variances in the backswing.
Hip Slide - avoid this common power leak in your golf swing.
Hip Over Rotation - use a 'left toe out' drill to correct over rotation of hips during the back swing.
Right Shoulder Drill - fix your club face at the top of your swing.
Two Club Drill - develop the perfect swing sequence.

Swing Plane & Path

Arc Width - Learn about the variances in arc width depending on position.
Shape of Swing - What's the shape of your golf swing?
Swing Plane - Do you have a flat swing?
Swing Path - Develop the correct swing path.
Club Path Effect - the effect of the club path on the target line.
Path/Face Speed - the relationship between club path, club face position, and the speed of your swing.
Rolling Arms - To help you keep your arms in the proper position.
Spine Angle - help you keep the proper spine angle.

Sources:

v1Golf.com