Printing on the back of paper

[ck1999]

I have about 300 excel files that when I print I want another page to be printed on the back of each file when they are printed. It there an easy way to do this besides placing the information in all 300 files.

For example
Filea.xls
Fileb.xls
Filec.xls
disclaimer.xls

I have a macro written in vba that calls for filea.xls to be opened and printed. What I am wanting is to print disclaimer on the back of the paper of filea.xls without having the person reverse the paper and then print disclaimer.xls. (Filea.xls, fileb.xls, etc. will all be only 1 page 1 side) The printer I am using does print two sides.
Does anyone have any ideas?

chris