Right then, it appears I will need a couple of things. I will need a project box for all the bits. A parallel cable to run from the Computer to the Project box, this in turn will connect to the Break Out Board. The Break Out Board will send a signal to the Controller Board I have and as m_c has said above the Controller board itself will need a 24volt supply which I can incorporate into the project box.
I spoke to Nick today about this and he also thought a relay might be required on the BOB if I want to control on/off of the spindle. So, all things being equal, does anyone have any suggestions as to which BOB I should buy? Ideally dual function because I could also use the board to turn the coolant on and off, maybe, perhaps? And will I need a power supply to the Break Out Board?

Thanks in advance.