I need to program a printer controlled by a siemens controller in step 7 over rs232 no idea where to start
Aaron, driving output to a printer is not the easiest task to accomplish in a PLC with ASCII over RS-232, but it can be done.
This link may be of some help: http://support.automation.siemens.com/WW/view/en/42002283.
The biggest issue is to be able to understand what your particular printer requires as far as data goes. You may also need to set up your printer in a particular way to accept ASCII commands.