© Ted Nasmith.
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Another wonderful reference book to keep at your elbow while reading the Tolkien classics is Robert Foster's The Complete Guide to Middle-earth. It is an excellent encyclopedia of all things Tolkien from A to Z. As many times as I have read The Lord of the Rings, I still find myself referring to the Guide to search all of the small details that make reading Tolkien such a delight.
The book is arranged alphabetically - A (Adalgrim Took) to Z (Zimraphel), and contains just about every Tolkien-specific reference imaginable. It is another indispensible tool to add to your Tolkien wish list. Don't leave home (or the bookstore) without it.
Of Special Interest:
Appendix A: A Chronology of the First Age. You say that you have trouble keeping all of the detail of The Silmarillion straight in your mind? Here is an invaluable tool to clear things up from the start to the finish of the First Age.
Appendix B: Genealogical Tables. Although these are essentially reproductions of the Tolkien tables, they are very much simplified and easy to read.