The hardcover version is the same as the softcover version except for the copyright page (the cover art is the same --- ignore the weird cover shown on lulu.com).
The hardcover version is available only from lulu.com, because to make it available worldwide I would need to get another ISBN and the book would be sold at the retail price (even by lulu.com), which is twice the wholesale price, and so the price would be close to 40 USD.
Ordering from lulu.com is slow, even for those in the US, since it takes them about 10 days to make the book.
The quality of the hardback is quite good --- rugged cover, and the binding appears to be sown and of good quality --- and the book lays flat(!).
Certainly, if you are recommending the book to a library, you should suggest they get the hardcover version.
Click here to go to the book on lulu (or go directly to lulu.com and search for Elliptic Curves).