Think Green! ;)
I'm often asked what a good website layout is, well the fast answer is make it user friendly, every page should be reachable with no more the 3 clicks from any page. Normally what I do is have a main page (the index page) then sub menus and from there the content pages in linked as shown in this example:
From Index have a link to each subtopic and back to index
From Each subtopic have a link to the sub pages
On every page have have a navigation menu (text link on top, bottom or in a side bar) that leads to index and subtopic 1, 2 and 3
For best results use text links and have the keyword you want to use in there.
When doing link exchanges have most pointed to your index but a few to some of the important sub pages also.
anybody wants to research a bit more
about site structures read this:
Search Engine Theme Pyramids
(See also the related links on that page on the bottom)