
I loved the Lord of the Rings, but I hated that I needed to refer to other sources such as the internet and books to understand some of it's lore. Let us be honest, I think about 100% of people who saw the movies and did not read the books fully understood what was going on during the movies.
The Interactive Guide to the Works of J.R.R. Tolkien could answer all of your questions as well as confuse you a little bit more. There are tons and tons of pages of information regarding the world of Middle Earth. You can learn about the Ents, or find out the difference between Saruman and Sauron.
If you are a hugely obsessive Lord of the Rings fan you will love this site. If you are like me and only like the movies but couldn't get past page 100 of The Fellowship of the Ring, you'll find this to be kind of laboring.