Here is a simple unregulated power supply for stepper motors.  Output voltage will ideally be  32.5VDC.  It uses a common 24VAC transformer.   I recommend the use of an AC line filter as it serves to filter high frequency noise associated with chopping drivers and motors.   It cost approximately $50 to construct.  Any time you are working with voltages encountered in a power supply, make sure to take appropriate safety precautions.

Parts List for a 32VDC 10A supply:

Power Transformer: MPJA 7846

FW Bridge Rectifier MPJA 5244

Fuse Holders MPJA 4476

DC Fuse (10A) MPJA 15784

AC Fuse (2A) MPJA 15779

Diode MPJA 5219

Switch DPDT MPJA 12220

Filter Capacitor 22,000 uf Sprague 36D223G050DC2A

Bleed resistor 1K 5W

AC FilterQualtek 858-06/011

Another route to building a power supply is my DCS1 pcb.  It utilizes a 10A rectifier, a pair of snap in capacitors, DC fuse and back emf diode, and also has two three terminal regulators that can be used.