\documentclass[9pt]{extbook}

\usepackage[usenames]{color} 
\definecolor{brown}{rgb}{0.4,0.28,0.15} 
\usepackage[colorlinks=true]{hyperref}
\hypersetup{
pdfauthor = {Devadatta and Yaj\~nadatta},
pdftitle = {My Magnum Opus},
pdfdisplaydoctitle = {true},
urlcolor = {brown},
pdfsubject = {Something},
pdfstartview = {FitH},
pdfpagelayout = {SinglePage},
%pdfpagemode = {UseThumbs},
%pdfpagetransition = {Dissolve}, 
pdfkeywords = {all, you, see, and, all, you, don't},
pdfcreator = {XeLaTeX: Minion Pro, Sanskrit 2003 fonts},
baseurl = {http://www.example.com}, 
pdfproducer = {XeTeX} 
           }

\usepackage{multicol}
\usepackage{ifxetex}
\usepackage{fancyhdr}
\usepackage[a4paper]{geometry}

\usepackage{url}

\pagestyle{fancy}
\RequireXeTeX
\usepackage{fontspec}
\setmainfont[Script=Devanagari,Mapping=itrans-dvn]{Sanskrit 2003}
\setlength{\topmargin}{1.00in} % real margin == this + 1in
\setlength{\oddsidemargin}{0.0in} % real margin == this + 1in
\setlength{\evensidemargin}{0.0in} % real margin == this + 1in
\setlength{\columnsep}{14pt}
\setlength{\columnseprule}{0.2pt}
\setlength{\headsep}{20pt}
\setlength{\headheight}{14pt}
\setlength{\columnwidth}{\pdfpagewidth/2}
\geometry{top=1.0in, bottom=1.0in, left=1.0in, right=1.5in}
\def\vr2{{\vspace{0.2cm}}}

\newcommand{\addline}{\medskip\hrule\medskip}
%\renewcommand{\chaptermark}[1]{\markboth{\MakeUppercase{#1}}{}}
%\renewcommand{\sectionmark}[1]{\markright{\MakeUppercase{#1}}{}}
%\renewcommand{\headrulewidth}{0pt}

\raggedright

\newcommand\myroman{\fontspec[Mapping=tex-text, Numbers=OldStyle]{Minion Pro}}

\newcommand\dn{\catcode`\^=11
            \catcode`\~=11
            \catcode`\&=11
           \fontspec[Script=Devanagari,Mapping=itrans-dvn]{Sanskrit2003}}

\obeylines

\begin{document}

{\dn

\centerline{\Huge shlokArdhAnukramaNikA}
%\pagebreak
%%\vr2
%\medskip\hrule\medskip

}

%\vr2

\vspace{0.3cm}

\addline

{\myroman
\copyright 2010 Devadatta and Yaj\~nadatta.
See \url{http://www.example.com} for more information.

}

\addline

\vr2

{\dn

\begin{multicols}{2} 

%\addline
\centerline{\Large a}

akampano.api rAxaso nishAcharesha choditaH

\end{multicols}
}

\end{document}
