What would you recommend as a starter hone? I have 4 blades, all of which came to me shave ready, so I just want something to practice with a cheap blade on, then refresh my current razors.

The key thing is I'm a grad student married to a teacher, I'm on an absolute shoestring budget.

What stone would you recommend, or would you recommend starting with micro abrasive films?

What's a good US source for affordable hones?