Some of my favourite books, that you can currently buy online for under £5 (click on link for to buy page):
Life of Pi by Yann Martel
One boy, one boat, one tiger ...After the tragic sinking of a cargo ship, a solitary lifeboat remains bobbing on the wild, blue Pacific. The only survivors from the wreck are a sixteen year-old boy named Pi, a hyena, a zebra (with a broken leg), a female orang-utan and a 450-pound Royal Bengal tiger. The scene is set for one of the most extraordinary and best-loved works of fiction in recent years.
Eric by Terry Pratchett
The Hobbit by J.R.R. Tolkein
The Left Hand of Darkness by Ursula Le Guin