`
\documentclass{letter}\topmargin=-1in % Make letterhead start about 1 inch from top of page
\textheight=8in % text height can be bigger for a longer letter
\oddsidemargin=0pt % leftmargin is 1 inch
\textwidth=6.5in % textwidth of 6.5in leaves 1 inch for right margin\begin{document}
\signature{NOME} % name for signature
\longindentation=0pt % needed to get closing flush left
\let\raggedleft\raggedright % needed to get date flush left\begin{letter}{DATI DESTINATARIO}
\begin{flushleft}
DATI MITTENTE
\end{flushleft}
\vfill % forces letterhead to top of page\opening{Dear Mr.}
\noindent Ph 1
\noindent Ph2
\noindent Ph3\closing{Sincerely yours,}
\begin{figure}
\includegraphics[scale=0.60]{firma.jpg}
\end{figure}\encl{CV} % Enclosures
\end{letter}
\end{document}`
Naturalmente devi caricare graphicx:
`\signature{\smash{\includegraphics{firma}}}`
Se poi ti serve anche il nome, usa un ambiente tabular dentro signature, ma caricando anche amsmath:
`\signature{\smash[t]{%
\begin{tabular}{@{}c@{}}
\includegraphics{firma}\\
Nome Cognome
\end{tabular}}}`
Ciao
Enrico