sprockets?

I am looking to get into CNC and I am in the process of building
myself a small router table. I will be using a trim router and some
stepper motors, Which are Fuji's NEMA 34 , rated at 150in/oz. This is
going to be a small machine with very limited capacity. It is just
going to be a learning tool, so no need to spend high dollars. Just
something I can play around with for the time being.

The stepper controller is a Camtronics.

I am looking for some sprockets and timing belts to drive a ACME
threaded rod and with a anti-backlash nut for the Z-axis. What would
be a good ratio from stepper to rod sprockets? 1:1, 1:2 The stepper
have a 180 S/R.

How thick of a timing belt should I be looking at? 3/8", 1/2" or ???

Thanks.