For 5k-10k and in general I would say
1.Tempos/fartleks/progressions
2.Hills
3.Sprints
4.Gym workouts
BUT it depends on the physiological demands of the event.
100/200/400-focus is on power development, mechanics, starts, relaxation at top speed. A touch of endurance for 400 meters, probably in the form of either 500-800m repeats much slower then race pace or 200s with short recovery, not a 10 mile run.
800-a LOT of ways to go with this one...you need a very good base, excellent mechanics, power development and great tactical awareness...chances are you will need to sacrafice some aspects of your training for others
1500m-An excellent base is crucial, power development is needed and tactical awareness is needed, mechanics also important
5000m Threshold and endurance work becomes much more important then 1500m-you cannot fake 12 1/2 laps of the track as you might be able to 3 3/4. Power development is needed but not crucial.
10000m-half marathon-Threshold work becomes key. For the 10000m fast track sprinting work is still needed but for a good half it is not necessarily needed.
Marathon-Endurance, Effeciency and Fat burning along with a fair amount of threshold work, some interval work and a 'dash' of pure speed.