No pressure on you, sorry if it sounded like there was.
What *has* happened (and still does) is that people buy books (new and/or from charity shops) and when they've finished with them they have offered them to the forum - i.e. names of interested people go into a hat and a drawer takes place, the winner is announced on the thread and PM's address details to the person with the book... and then receives it.
When you receive a book this way you add your name to the front so whoever reads it next can see the journey the book has made, and the book has something to discuss with the other books when it eventually reaches the Great Bookshelf in the Sky.
I've received a few books this way and have been happy to put them back into the forum wilds for the next person to pick up. I've also seen a couple of DVDs this way too....which reminds me, I think I may still have one of them which needs rereleasing!!