create an extra sidebar on some specific pages

I’ve designed my website and now on process of building it. I make it by using wordpress 2.9, the theme I am to modify is Zenlite 2.2.as I think it looks most alike my desired theme. I’m not sure if it’s possible to edit like I want to. Please see my website layout here. http://img38.imageshack.us/img38/4268/mweb1.jpg

my first and main page is actually one column oriented with a horizontal navigation menu. But I want to make an additional sidebar somes pages. And the additional sidebar should be able to show small thumbnails so that when clicking it show on the right side. Please see picture http://img94.imageshack.us/img94/3057/mweb2.jpg

seems like now I’m having two problems
1. to make a page with a extra sidebar (I don’t know how to set)
2. to make a graphic thumbnails (also have no idea how to do it)

It would be nice if anyone can help me with this. Thank you!