The best way (i.e. the best for me) to lower DC volage is to use a zener diode connected to a transistor. This will allow you to use higher current devices, since a largeer transistor can dissipate more heat than a small zener diode. It's usually cheaper than buying a large zener diode rated for the load. Of course, for 5,6,8, and 12V, I just use a LM7800 series IC. It has 3 pins: In, Out, and Ground. It's usually the cheapest way to go when building your own power supply.
