While LR is amazing for photography, I would not think of using it to produce books. I earn much of my living doing that and use InDesign for this. InDesign (or Quark really the tool to produce books.
Unless the book is a self-cover, you always have to make separate files for the cover and the interior. Typically you design the cover on one 'page' to include the back cover, spine, and front cover; and a second page for the inside back, spine and front. Often the cover is larger than the interior... so you do need woo press pdf's.
Within InDesign or Quark you can save pdf's in a variety of flavours including "smallest size" which is fine for checking the book on screen.