One of the greatest features in the Microsoft Office Suite of products is the ability to reference and link to any other document or file on your computer or network. I will run through a quick tutorial on how to link to another document from within Microsoft Excel.
To start, open your document. Select the cell to which you would like to hyperlink.
Then, click on the Insert tab followed by the "Hyperlink" button. You will see the following screen.
If there was text in the cell that you selected to hyperlink, then it will appear in the "Text to display" box. Otherwise, you can specify what you would like the hyperlink to say by adding text to the "Text to display" box. (eg., Click here to see the file)
Next, select the file that you would like to be hyperlinked. This can be done by browsing through the mini-Explorer window beneath the "Text to display" box. Once you select the file to which you would like to link, click the "Ok" button.
You should now be presented with a new blue link in the original cell you selected. If you hover over the selected cell you can see to where the cell is now linked. To go to the location, hold the Ctrl key and click on the link.
That's it! You have successfully created a hyperlink to a document in an Excel document.