Welcome to the useful links and downloads page!
As you're most likely well aware of, Christopher Awdry's books have been out of print for many years, as has his book Thomas the Tank Engine: The New Collection, a collection of his books. Wilbert's have been too, however they can be found in occasional Box Set releases or a rerelease of Thomas the Tank Engine: The Complete Collection (not so complete, eh?). With the way the rights holders have taken the franchise in recent years, it's unlikely we'll ever see another rerelease of their books. Along with that, Wilbert and George Awdry's Island of Sodor: It's People, History, and Railways has been out of print since 1992 (or 1987, depending on who's sources you trust), and Sodor: Reading Between the Lines is almost certain to never be reprinted, ever since the closure of Sodor Enterprises. Whilst this may just seem like an inconvinience, this greatly hinders people's ability to access and enjoy The Railway Series, limits younger ones from reading it, and casts important lore into obscurity. I hope to rectify this. On this page I have PDF copies for download of The Complete Collection, the New Collection, Island of Sodor, and Reading Between the Lines. For free! If Mattel so wishes to republish any of these publications, I shall be taking the link for that PDF down. Until then, enjoy!
If you are into audiobooks, or are looking for narration for your video adaptation, I highly recomend the YouTube channel Thomas Audio Archives, which archives very high quality and restored narrations of the books released on Cassette and Vynil. Narrations by Johnny Morris, William Rushton, Ted Robbins, John Geligud and more are hosted here, and are quite worth a listen!