actually fans dont draw much power. So you can run a bunch off one line. But the fan connectors on the mobo should only run 1 fan each.
I have a few controllers and usually you connect one 4 pin power to it, and than you plug the fans into the controller.
If you look at the fan it usually says how much power it needs, like .4A or .15A.
Most should be 12V, but if you want to slow them down (too much noise you can put a resistor on it to lower the voltage and make the fan more quiet.