Jose
You are using the incorrect terminology.
I think what you want to do, is the following two things:
1. You want to have more than one spreadsheet per workbook. Iow, you
may have a workbook (or then a file) named for argument's sake quotations.xls
In this workbook, you want several worksheets, or then spreadsheets, say one
called customers, one called stock and one called output.
2. You also want to be able to open several such workbooks or then files,
each containing several worksheets or then spreadsheets, by clicking on file
open once only.
To achieve the first, you can add worksheets to your workbook or file, by
clicking on Insert, Worksheet.
To achieve the second, open the files you want to open, by clicking on File
Open. Repeat this process till you have opened all the files you want to
open. Lets call them Book1.xls, Book2.xls and Book3.xls. If you want
Book2.xls to be on top everytime that you open these files, then open it
last. Once all these files are open, click on File and then on Save
Workspace. You will be prompted to name this workspace. You will notice
that it has the extension .xlw. Once you have saved the workspace, close all
these files. Now click on File Open. In you shortlist, you will notice the
..xlw space that you saved. Click on this, and all three your workbooks will
open.
HTH?