Ron, we just bought the same set and it is also missing instructions.  In fact, I logged on specifically to ask this same question.

As far as we've been able to figure out:

1)  You can only power one switch per outlet, even though the set comes with multiple switch tracks. 
2)  The switch track has to be close enough to where your power control hooks into the main track that they can share a controller.
3)  Our set came with tons of unneeded wires.  You only need the red wires with the exposed ends.

There is a black three-prong switch.  You plug into this switch two things:  one side plugs with the green wires from the switch track; the other side plugx with a red wire that has exposed ends.  The third prong on the switch stays bare.

Once plugged into the switch, hook that red wire into the controller, one exposed wire into each opening on the front of the controller.

The green and red wires can fit into either side of the control switch, but they only work if you magically pick the right side.  So, if you get it hooked up and it doesn't work, change sides of the switch.

I hope this helps.  The sets certainly are not user friendly.