Basic template for a letter in LaTeX

letter.tex

\documentclass[10pt]{article}

\usepackage{minibox}
\pagestyle{empty}
\setlength{\parindent}{0pt}
\setlength{\parskip}{\baselineskip}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{lmodern}

\begin{document}

\hfill
\minibox{42 West Road \\
         Cambridge \\
         Cambridgeshire \\
         CB1 1AB \\
         \\
         e-mail: \texttt{me@example.org} \\
         teL: 01223 123 456 \\
         \\
         24 October 2013}

\vspace{\baselineskip}

\minibox{1 North Road \\
         Cambridge \\
         Cambridgeshire \\
         CB2 2CD}

\vspace{\baselineskip}

Dear XXX,

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod 
tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, 
quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo 
consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse 
cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non 
proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod 
tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, 
quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo 
consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse 
cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non 
proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Yours sincerely,

\vspace{3\baselineskip}

XXX

\vspace{2\baselineskip}

\begin{tabular}{@{}l l@{}}
    \textbf{Enclosed:} & Attachment one \\
                       & Attachment two \\
                       & Attachment three
\end{tabular}

\end{document}