Now that you have a huge list of books your students (and hopefully you) will really want to read, it's time to get your hands on the books. Unless you're some kind of superstar teacher with an unlimited budget, chances are the funds for this project are small (or possibly even nonexistent). So how can you get free or cheap books for setting up your classroom library? Keep reading ...
1. Check out local thrift stores and libraries. They usually sell used books super-cheaply, and you may be able to find copies of books that would fit the mold you're looking to fill. You may even stumble across some cool finds that weren't on your list.
2. Go online. Search sites like Craigslist or Freecycle to find books people are willing to part with cheaply or for free.
3. Check out the library. You can sometimes get an extended check-out time for books from your school's library; however, if you try this, make sure you take extra care to make sure the books don't sprout legs and walk out of your classroom. Since you're the one checking them out, you'll be the one paying to replace them if they get lost or damaged.
4. Find community resources. When I taught in Baltimore, we had an awesome program in town called the "Book Thing." It was literally a place stocked with books that you could take for free. People would just donate their unwanted books and book lovers could get as many as they wanted, absolutely free of charge. Something similar could exist in your area, too.
5. Ask students for donations. Kids who read might be willing to donate books they've already finished reading.
Once your shelves are stocked, you're on your way to using your classroom library!