Yes, the plans explain everything.
The dynohub will charge a 6 volt battery quite happily once the AC power is rectified to DC - 12v charging is pushing it to the limits.
Remember max power from the dynohub is only 5 watts, so its only a starting toy really.
Yes, the motors we all use are of the permanent magnet variety, unfortunately they are a rare item. the rpm has to be approx 400 to generate 12+ volts
The Ametek range of tape drive motors are often used, and can still be found in the U.S - eBay is a good starting point (include U.S in search)
Plenty of other posts on this subject if you do a search, from my homepage.
If you are charging batteries by pedaling you have a better choice of motors, as they can be geared up.