Dave,
I am in the security field and have been using many type of card readers
for years. Track 2 is the most common track used for holding numbers.
There are Tracks 1,2 and 3. Tracks 1 & 2 are used on most bank cards.
To get track 3, you need a wider magstripe on the card. To change
tracks, all you need to do is move the read head up or down.
To get the pin out... well... it is usually black for ground and red for +5v
BUT... that is not always the case! I have seen wierd colour schemes.
If you can look at the circuit board for any type of electrolytic capacitor
or even a .1uf ceramic cap... these are usually used on the power lines
of the reader... also look at the chips.. see if you can find any datasheet
on any of the chips, that will tell you which pins of the chips are power...
just trace that out to the wires. Once you have identified the power...
just power it up and scope the other wires for the data/strobe signals.

Regards,
Josh