I have a Kindle (4th gen) .. got it for Christmas and absolutely love it. It's small, doesn't weigh much , yet reads just like a real book .. Ideal for on the Train, in bed, etc.. Fits in the pocket of my coat so I always have it with me, got about 10 books on it (mix of fiction, non-fiction, fantasy, thriller, "literature").. Kicking myself that I didn't get it sooner.
There's a lot of free books (legal) : http://www.gutenberg.org/ .
In the not so legal category I've yet to search for a certain book and not find it.