I found this question on google and found the solution to your problem (it is a bit late, but for everyone who is looking)
The page should look like this:
<html>
<head runat="server">
<title></title>
<link rel="Stylesheet" href="../Scripts/layout.css" />
</head>
<body>
<form id="form1" runat="server">
<div id="wrapper">
YOUR PAGE HERE
<div id="push">
</div>
</div>
<div class="footer">
YOUR FOOTER HERE
</div>
</form>
</body>
</html>
And in the 'layout.css' file (save it in the 'Scripts' folder in your website), add this:
.wrapper
{
width: 100%;
min-height: 100%;
height: auto !important;
height: 100%;
margin: 0 auto -20px;
}
.push
{
height: 20px;
}
.footer
{
position: absolute;
height: 20px;
width: 99%;
margin: auto;
bottom: 0px;
text-align: center;
}