Fortunately, I already knew that thrift stores in England are called "charity shops." I did a search for Oxfam stores (like Goodwill) in London and put about 10 of them on my xeroxed map of the city. That way when we were in that part of town to visit a museum or historical site, we could zip over to a nearby charity shop and look at their used books' section. A few of the Oxfam stores were just bookstores. I was thrilled to find vintage books in these places for 2 to 3 pounds. Even though that comes out to about 4 to 5 dollars, I was pleased to find some books on my wish list. They are more valuable to me as souvenirs than all the overpriced junk in the tourist shops.
(One of my favorite Oxfam bookstores was three doors down from the Eagle and Child Pub in Oxford, so be sure and look it up if you take a side trip to C.S. Lewis territory.)
Sadly, I did not find any Elizabeth Goudge titles, but consoled myself with a beautifully bound copy of Elizabeth Gaskell's Cranford (pictured above). It's a 1949 tiny blue hardcover printed by Oxford University Press as part of its World Classics. It's lovely to hold!
Previous posts on saving money in London are here (tours) and here (food).