If you just select Landscape the text will run across the full page, what I'd do is split the page into a couple of columns, using the Format/Columns menu item. Then you can tweak the layout with the Width and Spacing values (width of column and spacing between them) and other options, such as a line between the columns, can also be played about with in there. Changing the page's border sizes using the File/Page Setup menu item may also help with formatting.
Here's an example of what I mean:
http://myweb.tiscali.co.uk/lesrae/junk/example.doc
The main problem with this method is that you have to be clever with the page ordering to get it to work when folded up, or you have to cut the pages up.
Edit: I notice while playing with this that 2003 has an option to 'Book Fold' multiple pages under the Page Setup command, but it doesn't seem to do what it's supposed to on my machine - I'll have to play around with it a bit.