Thanks.
You're idea made me go back and search the dictionary for 'column' and I found more or less what I was wanting:
So this is now working like a champ in Microsoft Excel 14.4.8 on OSX 10.9.5.
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# Retrieve a list of items in a folder.
set fileNameList to list folder alias ((path to home folder as text) & "test_directory:Watch_Folder_Test:") without invisibles
# Convert the list of items to a list of lists.
repeat with a from 1 to length of fileNameList
set item a of fileNameList to {item a of fileNameList}
end repeat
# Append data to column A of the active worksheet.
tell application "Microsoft Excel"
tell active sheet of active workbook
set lastFilledCell to get end (range "A65536") direction toward the top
if value of lastFilledCell = "" then
set firstBlankCell to lastFilledCell
else
set firstBlankCell to get offset lastFilledCell row offset 1
end if
set cellAdrsLocal to get address local firstBlankCell
set AppleScript's text item delimiters to "$"
set {null, _column, _row} to text items of cellAdrsLocal
set newRange to _column & _row & ":" & _column & (_row + (length of fileNameList) - 1)
set value of range newRange to fileNameList
end tell
end tell
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Thank you to everyone for your assistance.