% example from : http://en.wikibooks.org/wiki/LaTeX/Letters
\documentclass{letter}
\usepackage{hyperref}
\signature{Joe Bloggs}
\address{21 Bridge Street \\ Smallville \\ Dunwich DU3 4WE}
\begin{document}
 
\begin{letter}{Director \\ Doe \& Co \\ 35 Anthony Road
\\ Newport \\ Ipswich IP3 5RT}
\opening{Dear Sir or Madam:}
 
I am writing to you on behalf of the Wikipedia project (http://www.wikipedia.org/),
an endeavour to build a fully-fledged multilingual encyclopaedia in an entirely
open manner, to ask for permission to use your copyrighted material.
 
% The \ldots command produces dots in a way that will not upset
% the typesetting of the document.
\ldots 
 
That said, allow me to reiterate that your material will be used to the noble end of
providing a free collection of knowledge for everyone; naturally enough, only if you
agree. If that is the case, could you kindly fill in the attached form and post it
back to me? We shall greatly appreciate it.
 
Thank you for your time and consideration.
 
I look forward to your reply.
 
\closing{Yours Faithfully,}
 
\ps{P.S. You can find the full text of GFDL license at
\url{http://www.gnu.org/copyleft/fdl.html}.}
\encl{Copyright permission form}
 
\end{letter}
 
\end{document}
