These 8 books are the primary and most reliable sources for Bruce Lee's words. As literary executor for the Bruce Lee estate, Mr. Little had access to Mr. Lee's library and the Lee family.
The first title, Bruce Lee: Words of the Dragon: Interviews, 1958-1973, might be more appropriately called "words about the dragon" rather than "words of the dragon." The book consists mainly of stories by reporters about Bruce Lee. The text does include a story written by Bruce Lee, published in a Taiwan newspaper, however.
This is one of the easier titles in the library to read cover-to-cover. As it is organized by date of publication, it follows Lee's life chronologically. It can be somewhat jarring to encounter the stereotypical and racists attitudes adopted by some of the reporters. This is a good book to read if one wants to get a sense of what the outside world thought of Bruce Lee during his lifetime.
Bruce Lee published a book called Chinese Gung Fu: The Philosophical Art of Self Defense in late 1963. This was the only title he wrote and published during his lifetime (despite what you may have seen in the fantastical 1993 movie "Dragon: The Bruce Lee Story.") He had planned to write a longer book about Gung Fu, but stopped working on it in 1965.