Well, 'Wikipedia' told me all I needed to know about history and other sites provided stills and video. Being a cartoon engine, 'Ivor' has, shall we say, rather unusual proportions for a steam locomotive but quite a faithful recreation has resulted from the restoration of a small, 4-coupled, outside cylinder Peckett, works number 1555. I believe this locomotive is one of two which worked in Cawdor Quarry, Matlock (right next to the Peak Rail line, where I regularly drive).
The locomotive owner, Steve, was on hand as Ivor pottered around the station and characters from the story like Dai Station, Mrs. Porty and driver Edwin Jones performed little playlets. From time to time, Ivor would couple up to the two-car DMU for a romp part way up the line. It was all good fun and passenger numbers were healthy enough for Ivor to have a repeat booking in 2008. A 'special' was run at the end of the day on the 4th August and there's a Video Clip of Steve driving his engine.