\documentclass[12pt]{article}
%\textheight 210mm
\textheight 218mm    % textheight is actually 210mm,
\topmargin -3.1mm    % this is to get header in
\textwidth 145mm
\oddsidemargin 9.6mm
\evensidemargin 9.6mm
\begin{document}
\parindent 0mm
\parskip 12pt
\thispagestyle{empty}
\renewcommand{\thefootnote}{\mbox{$\fnsymbol{footnote}$}}
\renewcommand{\footnoterule}{ }
\newcommand{\Today}{\today \typeout{** Warning:
Letter is dated with today's system date.}}

\newcommand{\Header}
{ \vspace*{-17mm}    % this is to get margins right
{\Large \rm Your Company Ltd.}
\medskip \smallskip \hrule \medskip
\footnotetext{ \normalsize
\medskip \hrule \bigskip
\noindent
Your Department, Your Company,
Your Road, City 1\\
Tel: (01) 9999999, Fax: (01) 8888888,
E-mail: youremail@mail.com
}
}

\Header

\renewcommand{\thefootnote}{\mbox{$\arabic{footnote}$}}

\begin{tabular}{@{}ll}  % the @{} removes space before first item 
Date: & \Today \\
 & \\ 
%%%%%%%%%%%%%%%%%%%%% ADDRESS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
To:  & Addressee, Address Road, Address St. Address Town. \\ \typeout{** CHANGE ADDRESS}
     & Fax: (01) 9999999   \\ 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 & \\ 
From: &  Sender Name \\
 & \\ 
%%%%%%%%%%%%%%%%%%%%% SUBJECT %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Subject: & Reason for Fax \\
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 & \\ 
%%%%%%%%%%%%%%%%%%%%% CONTENTS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Contents: & 3 pages (including this page) \typeout{** 1 PAGE FAX OK?}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\end{tabular}

%\textheight 210mm
\textheight 208mm     % fix for the text length


\medskip\smallskip
\hrule
\medskip
%%%%%%%%%%%%%%%%%%%%% MESSAGE %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Hi  

Please find the blah blab blah this is the cover sheet so two more pages you add.

Thank you,

Your Name

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\end{document}
