I have recently finished making a mill table power feed following the design shown by Myford Boy on Utube.
It has already been useful and I am very pleased with it. I purchased the 36volt power supply, Nema 23 stepper motor, driver and controller all from EBay, with a total cost of £62. Luckily I already had the pulleys and belt. As I need a power supply for my lathe toolpost drill, I have made the power supply self contained and use connectors to attach to either.
It is a good, simple design which I would recommend but I had to strengthen the motor mounting plate to stop it flexing.
On/Off, speed and reversing are all from the controller box attached to the pulley case.
For safety, I need to fit limit switches and label the controls. I have some photos in my album.
Mike