.007 is straight prose, whereas Awdry did devise the accompanying illustrations, and the idea of faces on the locomotives. Awdry actually did the first illustrations himself, but he was no artist and the publisher arranged for a proper artist to redo them.
Gerry Fiennes, in his classic railway management book "I Tried to Run a Railway", writes that he originally called it "Yje Fat Controller", and asked Awdry who agreed, but Ian Allan, as Fiennes' publisher, rejected it.
It is my understanding someone else did the original illustrators but Rev Awdury wasn't happy as they didn't look accurate enough for a steam engine, so he had them redone. If I've misremembered this, do correct me. Not got the biography to hand, as I'm on a train no less!
The originals are worth a lot as they have never been republished.
Rev Awdury started charging preserved railways to use his characters in the 80s as he felt they were making money off it. He then sold the stories on to a company After that he regretted it, as he felt it all went to commercial.
Thomas was popular in this books but his stories were the Railway Series and not Thomas the Tank Engine and friends.
Rev Awdury stopped at book 26 and had intended to title the next one Really Useful Engines. When his son Christopher took over, he did title it that, apparently unaware that it was the title his father had been thinking of using. The original book was stories Rev Awdury made up to tell his son when he was ill. Someone suggested he have them published. Well done that person.
If anyone can find them second hand, that is the 1960s audio recordings of the stories read by Jonny Morris and later William Rushton, they are worth getting hold of. I think they stop at book 14. At one stage DECCA issued them on LP. Buy I have some 7"s issued by another label.
Not aware of them having been reissued on CD. I'm guessing the current owners aren't interested and the original owners don't have rights to do so.