Charmion, how do you organize your books?

My father kept a three-ring notebook with typed and handwritten pages in his car. He was always stopping at bookstores and used book stores and wanted to keep track of what he'd already read. The list was long; I sold a lot of mysteries from his estate on eBay and they often went as sets because he would get every one from his favorite authors. I also like mysteries, but decided I would do better to clear out the huge volume of books and if I choose to read these authors at a later date, I'll get them via the library or interlibrary loan or online. Nowadays there are sites like LibraryThing that Katlaughing used, and GoodReads, probably an independent company at one time but now owned (to no surprise) by Amazon. It lets you transport the list of all of the books you've purchased into GoodReads (you can choose whether they appear or not, and mark them read or not.) I suspect he would have enjoyed keeping track of his books that way. And in order to know I'm getting my books in the correct order, I use Fantastic Fiction, a site out of the UK that I discovered when I was selling those books.

I've thought about using LibraryThing to keep track - I think you can get a lifetime membership for a fairly low cost, then catalog all of your books by ISBN. When I organized my front room last (one 14' wall is floor to ceiling books) I pulled them all off of the shelves and used the large tiles in my den as an organizer. One tile for As, the next for Bs, and using a couple for letters that had more last names (S, T, M, etc.) I was able that way to look at each stack and cull the duplicates. But it doesn't give me a list of everything, just one of everything.