Cheap books can be found in sales, for example, car boot sales and bookstalls on markets. There are several shops that sell second-hand books, some of which are specialist book shops, and others charity shops such as Oxfam or Barnardo's. You can also purchase some remaindered books in shops that specialise in this field or else, you can search on the internet.
Most cheap books that you can buy are second-hand. These can be picked up in a range of places. Some market stalls, particularly in university towns, sell second-hand books.There are also smaller stalls at car boot sales and jumble sales. Occasionally, a university students' union will organise an end of term sale for students who wish to be rid of course books that they no longer need. Here, you can buy used course textbooks and others.
Second-hand book shops can also be good sources of cheap books. You can find some of these in university towns such as Cambridge. However, cheap does not always mean very cheap, and some second-hand books can sell at quite high prices if the books are considered antiquarian, first editions or signed by the author.
Charity shops such as Oxfam or Barnardo's often sell books quite cheaply. This is the case with children's books and paperbacks. You also have to consider quality. Some books may be in excellent condition, whereas others may be quite shabby. Obviously, the ones in poorer condition are sold cheaper.
One good source of cheap book deals are shops or sites that sell remaindered stock. Remaindered stock is stock that publishers want to be rid of. Perhaps, they have printed too many copies of a book which have been lying in their warehouse for a long time and they want to clear space for newer works. You can often purchase remaindered books at the best prices.
You can tell when a shop selling remaindered books. The books are obviously new, but are more cheaply than you would expect. Many of their books are quite popular, and you do not get specialist academic or rare works here. Sometimes websites sell remaindered books. You sometimes see books on Amazon going for a penny including the post and packing. These are remaindered works.
Some shops will sell damaged works more cheaply than others, for example, books which have pages and the cover turned up, but still have perfectly readable text
Internet book-sellers such as Amazon, are sometimes the source of cheap books. Amazon only sell books in at least acceptable condition. Private sellers are able to sell their unwanted books on Amazon, and sometimes they go quite cheaply.