----------------put this code in body tag--------------------------
<div >
<iframe src="https://www.facebook.com/plugins/like.php?
href=http://www.dotnetfunda.com/Home.aspx&layout=standard&show_faces=true&width=400&action=like&colorscheme=light"
scrolling="no" frameborder="0" style="border:none; width:250px; height:80px"></iframe>
</div>
Note: write your site name in place of www.dotnetfunda.com and then write site home page name, which page you want like .