Have just been in Home Bargains (Skelmersdale) and found this book for £1.99. My 14 year old loves the Eragon series but this is a bit young for him, it's like the Dragonology/Wizardology/Pirateology series.
Had a quick look on Amazon and Play and this book is around the £10 mark on both.
I've bought it for my less bookish 9 year old. It might persuade him to have a go of the actual books too.