I don't buy books often, but when I do, I get them at BMV!
This place is cozy and when you walk in, it seems like a store you'd find in Diagon Alley of the world of Harry Potter. There are great finds with great prices, please don't waste your money paying for more at Indigo across the street.
BMV also buys used books, depending on what they consider resell-able. A woman walked in with a box of books, and was paid $45.00.
Definitely a fan!