How do i add a drop down!!

Hi Guy's,

Im having a right mission here and could really do with a bit of help! Im trying to implement a drop down menu on the main navigation smack in the middle of the page above the Jquery slideshow!

Could someone give me a bit of guidence on how i can add this??

http://sowebservices.co.uk/Chocolate5/

HTML:

Below is the CSS for the menu:

#menu ul {
	margin: 0;
	width: 900px;
	padding-top: 0;
	padding-bottom: 0;
	padding-left: 100px;
}

#menu ul li {
	float:left;
	list-style-image: none;
	list-style-type: none;
	height: 30px;
	padding-top: 0;
	padding-right: 10px;
	padding-bottom: 0;
	padding-left: 10px;
}

#menu ul li a {
	float:left;
	font-size: 12px;
	letter-spacing: 1px;
	text-decoration: none;
	height:20px;
	display: block;
	padding-top: 5px;
	padding-bottom: 5px;
	padding-left: 10px;
	color: #FFFFFF;
}

#menu ul li hover {
	float:left;
	font-size: 12px;
	letter-spacing: 1px;
	text-decoration: none;
	height:20px;
	display: block;
	padding-top: 5px;
	padding-bottom: 5px;
	padding-left: 10px;
	color: #945A30;
}
.selected {
	background-image: url(../images/menu-bg.gif);
	background-repeat: no-repeat;
	background-position: right top;
}

li.selected a {
	background-image: url(../images/menu-abg.gif);
	background-repeat: no-repeat;
	background-position: left top;
}

HTML:

If someone could give me a hand that would be fab ;-)

Regards

Tom