The SolverTable function shows up in Excel under the Data menu item.  When you install SolverTable as an Excel Add-in, all you are doing is telling Excel where to find the two files SolverTable.xla and SolverTable1.xla, both of which should be in the same directory.  (Note: make sure the extension you download is .xla, not .xls)

If your computer does not already have these two files, then either download them to your school computer (in an easy to find location, such as the desktop)  using the above links or place them in a folder on your school P: drive for easy access. 

Simple Process for Loading Solvertable into Excel.
1.  Download SolverTable.xla and SolverTable1.xla to a location that is easy to access (e.g. the Desktop or a folder on your desktop).  To download, simply right-click the above links and choose Save Target As -- make sure the filename extension is .xla -- sometimes Microsoft changes it to .xls.
2.  Go into Excel, under Tools->Add-ins, Browse to the location of SolverTable.xla (not SolverTable1.xla) select it and click OK (see below).

3.  SolverTable should now appear as an item under Excel's Data menu!

Possible problems & solutions:
A.  After installing SolverTable, it does not appear under the Data menu or there is an error message.  Try quitting Excel and then opening it again (if this doesn't work the first time, don't endlessly quit Excel and restart it, try one of the other fixes).

B.  You cannot find SolverTable.xla when you go Browsing to add it in.  It is possible that during download, Microsoft changed the filename extension from .xla to .xls.  If this is the case, simply change the filename extension back to .xla.  If you cannot see the filename extensions, click here for simple directions on fixing that.  Alternatively, download the files again and make sure the extension is .xla.

C.  When you click on Data --> SolverTable you get an error message saying SolverTable was not found at a certain location.  Remember that location and copy SolverTable.xla and SolverTable1.xla to that location and try again.

D.  Follow the directions from the author of the book & SolverTable (although I would skip step 3 for downloading/installing from his web site -- you already have these files from your textbook or the above links).