\documentclass[stdletter,cellowindow]{newlfm}
\nameto{Ura Belcher}
\addrto{123 Belch Street \\ Belcherville, VA}
\namefrom{Me Person}
\addrfrom{123 Personstreet \\ Personville, VA}

\begin{document}
\closeline{Sincerely yours,}
\greetto{Dear Mrs. Belcher,}
\begin{newlfm}
What up?
\end{newlfm}
\end{document}