One book that is good and easy to understand is The Universe in a Nutshell by Stephen Hawking. Lots of diagrams and stuff. There are lots of good books by Dr. Michio Kaku, on various topics in physics. You could also read articles on physics post. There was some quote I found, I don't know who said it but it goes like this: Whatever you learn with enjoyment you will never forget... Something like that.
http://www.hawking.org.uk/
http://www.mkaku.org/
http://www.physicspost.com/