I am working with 3 separate mailing lists stored in 3 excel workbooks. I
want to keep separate files, but occasionally need to combine all three into
one file or workbook to do a large mailing. Do I have to create a fourth
workbook and copy and paste the three existing files to create one large
file? Or, is there an easier way?

At the moment, I'm unable to take the excel online tutorial because I am
currently working on a machine at home that has an older version of excel.
However, the excel files I'm trying to combine are on my machine at work that
has windows xp professional. I can access the tutorial fine when I'm at
work, but not on my home machine for the reasons stated.

Can someone provide some guidance, please? Thank you.