HTML Code:

<a href='http://JavaScriptsandmore.com/' class='button'>JavaScript's and More</a>
<a href='http://Google.com.com/' class='button red'>Google</a>
<a href='http://bing.com/' class='button large green'>Bing</a>


CSS Code:

.button {
    padding: 5px 10px;
    display: inline;
    background: #777 url(button.png) repeat-x bottom;
    border: none;
    color: #fff;
    cursor: pointer;
    font-weight: bold;
    border-radius: 5px;
    -moz-border-radius: 5px;
    -webkit-border-radius: 5px;
    text-shadow: 1px 1px #666;
    }
.button:hover {
    background-position: 0 -48px;
    }
.button:active {
    background-position: 0 top;
    position: relative;
    top: 1px;
    padding: 6px 10px 4px;
    }
.button.red { background-color: #e50000; }
.button.purple { background-color: #9400bf; }
.button.green { background-color: #58aa00; }
.button.orange { background-color: #ff9c00; }
.button.blue { background-color: #2c6da0; }
.button.black { background-color: #333; }
.button.white { background-color: #fff; color: #000; text-shadow: 1px 1px #fff; }
.button.small { font-size: 75%; padding: 3px 7px; }
.button.small:hover { background-position: 0 -50px; }
.button.small:active { padding: 4px 7px 2px; background-position: 0 top; }
.button.large { font-size: 125%; padding: 7px 12px; }
.button.large:hover { background-position: 0 -35px; }
.button.large:active { padding: 8px 12px 6px; background-position: 0 top; }