I was at the Heilsarmee Brocki near Bahnhof Hardbrücke in Zurich today and they have a whole table filled with English books. About a dozen boxes. I picked up a couple of paperbacks for 2 francs each.

Usually they only have a shelf full, so check it out if you're so inclined.

St Andrew's Church in ZH has an English books sale each year. I travel a lot so was there only one year but was impressed with the range of books (and the prices were very reasonable)

That's great! Usually I hunt for the books in Brocki near Bahnhof Enge, but this one is much closer to my place.