Nineteen Eighty-four

I have to recommend a book here, Nineteen Eighty-four by George Orwell.

If you live in Argentina, Australia, Canada, Oman or South Africa, you can get it for free under public domain.  (See Wikipedia section on copyright status in the EU.)

If it's legal in your region: Download available from Project Gutenberg Australia (you have to scroll down a bit to get to George Orwell):

If it's not legal in your region: According to Wikipedia, in the EU, it will still take until 2020 until it's in the public domain (and of course, the EU may be lobbied to extend this date).  You could of course just get it from the bookstore... (e.g. Amazon, Penguin Books, or just your local bookstore, of course — I'd put a link if I could.) It's a classic, so you can get it really cheap.

Language: The book is written in understandable English, even for non-native speakers.  If you still feel uncomfortable about it, it's translated into more than 60 languages.  There is no excuse for not having read it.