How to move the sidebar under a main image

I have a quite normal fixed (front) page starting with a header and a menu – before a title, a main picture and then the let’s say the “main content”.
Now I would like to place the sidebar to the left below the main picture, on the side of the main content. The sidebar will be quite short, so the very best would be if the main content could flow down the side and then in beneath the sidebar.

I’ve tried to make a template just for this page (page2.php) and I’ve managed to put the sidebar (a sidebar2.php) in quite well in the right place inserting some css in the style.css file. But I’m confused about how I can place the sidebar call in the page2 file to make it work.
(I’m also in doubt of which details to provide as a start.)
Anyone who can help me?
Kjetil

The site is dolcevita.no (just moving it live from its hide-away at dolcevita.no/wp) and I’m just talking about the front page.
For now the page is built without this (just used tables), so the “2” part of the CSS below is left out on the server.
(e.g. #center is for the other pages, #center2 is for the front page)

#center{
	float:left;
	width:635px;
	background:#fff;
	margin:10px auto
}
#center2{
	float:right;
	width:635px;
	background:#fff;
	margin:10px auto;
	padding-top: 10px;
}
#Sidebar{
	width:255px;
	margin:35px auto 10px;
	float:right;
	background:#fff
}
#Sidebar2{
	width:255px;
	margin:400px auto 10px;
	float:left;
	background:#00FF00
}