Autocad drawing linked with excel sheet data

Dear sir,
I have lots of autocad drawings of same template. I have an ms excel sheet with the required data (Dimensions etc) to be incorporated on to the drawings. How can I do this by linking the sparead sheet to autocad drawing.
Secondly, I want to know how to incorporate changes made in a template drawing (lines,shapes, colors etc) to get automatically updated in all drawings.
Thanks.