Help! I need more books!

I'm starting to think that even after I get the rest of my books from my parents' basement, my books will still not fill the shelves of my library, much less the freestanding bookshelves I have in the living room and dining room. How did this happen? I pride myself on being such a bibiophile and yet I can't fill floor-to-ceiling shelves in one lousy room. :(