i am looking to buy a Cummins mini mill (http://www.cumminstools.com/browse.cfm/4,1485.htm) and i would like to make it CNC but i have some questions about it.

Frist off what do i need to make it CNC i have read alot of different parts and ways to do it what is the best and longest living. i woul dlike the know the parts from the from the computer on (i can handle the computer) and if you can post links that would be great.

questions about the parts that i have read about.

Steaper motors vs. Servos are those the same thing, is a stepper motor a more definded name for a servo and if not what is the difference?

leadscrews is this just another way to move the table? and why are they so expensive?

how does the mill/computer tell whats to far (ex. it drilling though the table and it thinking it is just tuching the materal)

and lastly i have read about some people putting cooling systems on there mills. is this a must or is it just a good thing to do and how do they work are the water cooled. air cooled, freeon cooled??

Thanks in advanced
Mike