Clearing page style, but adding on page number

   \documentclass[11pt,a4paper]{article}
\usepackage[T1]{fontenc}
\usepackage{lipsum}
\usepackage{tocloft}
\begin{document}

\tableofcontents
\thispagestyle{empty}
\newpage

\section{Preface} %want section number to be 0
\thispagestyle{empty}
\pagenumbering{roman}
\lipsum[1-3]
\newpage

\section{Start From Here}
\lipsum[1-5]

\section{And So On...}
\lipsum[1-5]
\end{document}


Currently I have page numbering and title in the header and for both the header and footer I have a line (I'm not sure what it's called). For the preface, I want all of that gone, which is why I used \thispagestyle{empty}, but I do want a roman page numbering in the bottom center.

How can I get the page numbering on the preface to show a roman numeral? (As of now it only shows in ToC).

-
How do you get page number and title in the header? A viable solution needs to know this information. –  egreg Apr 8 '13 at 8:18
Now that the problem has been solved, perhaps you should add again the relevant information about your headers/footers; by the way, did my answer solved the problem? –  Gonzalo Medina Apr 8 '13 at 12:56

You can define a new page style using \fancypagestyle{<name>}{<commands>} to get rid of other headers/footers and leave the page number, and then use \thispagestyle{<name>} at the desired locations:

\documentclass[11pt,a4paper]{article}
\usepackage[T1]{fontenc}
\usepackage{lipsum}
\usepackage{tocloft}
\usepackage{fancyhdr}

\fancypagestyle{myplain}
{
\fancyhf{}
\renewcommand\footrulewidth{0pt}
\fancyfoot[C]{\thepage}
}
\fancyhf{}
\fancyhf{}
\pagestyle{fancy}
\renewcommand\sectionmark[1]{\markboth{#1}{}}%don't move this

\setcounter{section}{-1}

\title{The Title}
\author{The Author}
\makeatletter
\let\hdrtitle\@title
\makeatother

\begin{document}

\tableofcontents
\thispagestyle{empty}
\newpage

\section{Preface}
\thispagestyle{myplain}
\pagenumbering{roman}
\lipsum[1-3]
\newpage

\section{Start From Here}
\pagenumbering{arabic}
\lipsum[1-5]

\section{And So On...}
\lipsum[1-5]
\end{document}


The solution above will work if the preface is one page long; if the preface spans more than one page, you could define two styles: for example, myplain (with only the page number (I assumed it should be centered in the footer, but you can easily change this)), and myfancy (with your header/footer and rules); then you can use \pagestyle{<style>} at appropriate locations to switch styles:

\documentclass[11pt,a4paper]{article}
\usepackage[T1]{fontenc}
\usepackage{lipsum}
\usepackage{tocloft}
\usepackage{fancyhdr}

\fancypagestyle{myplain}
{
\fancyhf{}
\renewcommand\footrulewidth{0pt}
\fancyfoot[C]{\thepage}
}
\fancypagestyle{myfancy}{
\fancyhf{}
\pagestyle{fancy}
\renewcommand\sectionmark[1]{\markboth{##1}{}}%don't move this
}
\setcounter{section}{-1}

\title{The Title}
\author{The Author}
\makeatletter
\let\hdrtitle\@title
\makeatother

\begin{document}

\tableofcontents
\thispagestyle{empty}
\newpage

\pagestyle{myplain}
\pagenumbering{roman}
\section{Preface}
\lipsum[1-10]
\newpage

\pagestyle{myfancy}
\pagenumbering{arabic}
\section{Start From Here}
\lipsum[1-5]

\section{And So On...}
\lipsum[1-5]
\end{document}


Perhaps you could be interested in using the book document class and its \frontmatter, \mainmatter, \backmatter commands? (using \chapter as the high level sectional unit, of course).

-
but that doesn't clear header and footer in the preface? –  AlanH Apr 8 '13 at 2:54
@AlanH please see my updated answer. –  Gonzalo Medina Apr 8 '13 at 19:51