I'm having an argument with my bookshelves.
Or with my books. I'm honestly not sure which.
We have some books, and pretty much no organizational system whatsoever.
A while back, I decided to move all of our series of books to one bookshelf. This thing is 6' tall and 3' wide (much like myself) and it is FULL of books that have more than one part. One and a half shelves are all Wheel of Time, and there's Tolkien, The Spiderwick Chronicles, The Girl With the Dragon Tattoo stuff, and on and on. In fact, it is so full that the Harry Potter series is ON TOP of the bookshelf, with our cute little Harry & Hermione bookends and everything by Piers Anthony is on another bookshelf all together, even though there are 2 different series by him over there. He's over on another bookshelf of the same size that I've decided is for "books by the same author, though not necessarily in any kind of serial format." By that logic, I should move the 2 Dean Koontz series off the series bookshelf and move them over there, but Dean already has 2 whole shelves because I'm a sucker for his work and I can't see making it 3 shelves.
But there you have sort of the extent of my organization. Books in series are segregated (mostly) and if we have more than one book by a particular author, those go on a separate bookshelf as well. I sort of have some... thematic shelves. The "all things Ireland/Norse mythology" shelf and the "bibles and stuff about God & Jesus, including Christian fiction" shelves. There's sort of a "fantasy/sci-fi" shelf, but all J's Star Trek books are on another shelf, next to the books we kept from classes, because what I really need just now is a handbook on screenwriting and broadcast voice techniques.
Which leaves many shelves full of just... books. In no order. Not grouped by subject or genre because I can't figure out where to put a book about a woman who goes to the Amazon to find a fellow researcher and winds up sleeping with her presumed-dead co-worker, even though she spent the first half of the book telling us that she would never, ever do that because she wasn't that kind of woman. Next to the one about a woman who does nature-research-type stuff and I think there was a romance involved, and does she get pregnant? I can't remember. Those books are just sort of... out there.
I suppose I could do like stores and libraries do (not with the Dewey Decimal system or anything, unless Tara wants to come do it as a project for her grad school), but put things in alphabetical order by author.
That smacks of effort.
If you want to borrow a book that's not by an author that we have lots of books by, or part of a series, you're just going to have to look at a lot of shelves.