I took on of the track turnouts apart and it is indeed a pair of solenoids with a metallic shaft running through the center of the pair. By powering either one of the solenoids causes the magnet field to draw the shaft one way or the other. The shaft itself is connect to mechanism to throw the track frog (rail). Also, I do believe a DC current flowing in either direction will magnetize the solenoid.
I did put multimeter on the AC coming out of the powerpack and it is amazing 17 volts for these little solenoids. For those who had warnings, my circuit uses optocouplers to isolate my external DC power from the arduino circuit. See my fritz link in my previous post for circuit layout.
Here's the Fritz off my circuit; warnings it harry! Each of the pair of wires going to the motors would be an example of a pair that would need to go to the 3 wire solenoid pairs.
http://fritzing.org/projects/train-track-and-turnout-control-system/
Therefore I need to design my 2 wire DC (with forward or reverse current) into the 3 wires of of solenoid pair. I think I can put diodes on each of the 2 main wires to the solenoids, have one diode forward and the other diode in reverse. Then send one of my DC wires to the pair of diodes, and the other DC wire to the common. When the DC goes forward or reverse it should only go through one solenoid or the other. See my attached image as example.
I've yet been able to get the opportunity to wire this up and test it, but the online circuit simulator shows one bulb or the other to light when DC goes one direction or the other.
