I'd do this in two steps.  First, record the opening of a specific file.  
Then edit the resulting VBA code, replacing the Filename:= parameter to
incorporate the variables provided by the user.  You'll probably use the &
operator to combine some fixed components with some variables along with the
format operator to turn the input date into the appropriate file name,
something like
Filename := "S:\" & CompanyName & "\" & DivisionName & "\" &
text(Date,"mmddyy") & ".txt"
Along the way you can also use the immediate window in the VB Editor;  type
the work print followed by the right-hand side of the equation above to see
that you get the expected path and filename.
--Bruce

If you just want to open the text file you should use the following command
in your VBA:

   Dim sCompany As String
   Dim sDivision As String
   Dim sDate As String
   Dim sFilename As String

   sCompany = Range("A1")
   sDivision = Range("A2")
   sDate = Replace(Range("A3"), "/", "")
   sFilename = "C:\" & sCompany & "\" & sDivision & "\" & sDate & ".txt"

   Workbooks.OpenText Filename:=sFilename

In the above example you should replace C:\ with the starting point of your
folder structure. You'll notice Replace(Range("A3"), "/", "") this ensures
that if the date is entered dd/mm/yyyy or mm/dd/yyyy ie. with slashes, which
are invalid for filenames, then  they are removed.

I hope this helps.