Did you get it all sorted Sneaks? For mine I wrote it all separately, but to combine it all I just copied and pasted each chapter into the big document, including all the formatting and there were few issues.
Its possible to use section breaks to insert a landscape page, but be careful of the page numbers when it comes to that point, you need to fiddle around a bit to get them in the right position for when the page is printed. Also if your margins are not equal like in my uni (left margin bigger for binding) then you need to check the page number is in the right side for when it's printing, I had to change mine after it had been to sent to the printers and they called to say it was coming out upside down.

I've got it sorted for now. I'm dreading page numbering etc. but will sort that later I think (sprout)