J.R.R. Tolkien 4-Book Boxed Set: The Hobbit and The Lord of the Rings (Movie Tie-in): is $21.50 at Amazon today, and eligible for free super saver shipping or free shipping with Amazon Prime.
That comes to only $5.37 each, per book, shipped!
The 4-book set includes:
The Fellowship of the Ring
The Two Towers
The Return of the King