I buy most of my books used from charity shops. I'm on a pretty tight budget and I read so many books(I can read 3 or 4 on some days) that I couldn't afford to buy new.
I also make use of the library, and Kindle deals. What I also love about second-hand books, besides getting a bargain, is the element of surprise. I never know what I'll pick up, and I've found so many on my wish list in charity shops.
I appreciate that authors deserve to be paid too, so if I really like a book then I'll probably buy a Kindle version, or a copy with a very beautiful cover, or just a hardback, but I can't afford to buy new all of the time. If I go to an independent bookstore then I'm happy to buy new.
Which do you prefer?