bj, you're correct insofar that Firefox and related allows you to resize font-sizes specified in pixels, but IE wont change the size of the font...so that's a huge audience you don't have to worry about.
My results come out almost identical to Fatanfx's example above...so sorry for the redundancy. Of course you will want to place the CSS in an external file for optimization and future update purposes.
<head>
<title>Blue Button Example</title>
<style type="text/css">
a.button {
display: block;
width: 85px;
height: 14px;
padding: 6px 0 8px;
font-family: Arial, sans-serif;
font-size: 11px;
font-weight: bold;
text-align: center;
text-transform: uppercase;
text-decoration: none;
letter-spacing: 1px;
color: #FFF;
background: #55298A;
}
a.button:hover {
color: #000;
background: #EEE;
}
</style>
</head>
<body>
<a class="button" href="#">Home</a>
</body>