English electric locomotives

Are there any books/sites that have a chronological history of the early English Electric diesel locomotives (or for that matter British early diesels, especially export)
The Aussie first main-line diesel was an EE although it was really home built with EE components, and EE (including other makes of early nosed-diesels) were used world wide, but unlike some books or sites on same period U.S. locomotives finding something on the British locos. is very difficult.
The few site I have found usually have a narrow scope.

New zealands first three diesel locomotives were english electrics . the de class was more of a road switcher style , brought in the 1950's they hung on till the 90's as shunters . the df was next a double cab , 1500 hp mainline machine that was quite heavy . they only lasted till the 70's , not quite sure why . next were the DG class , these were only 750 hp , single cab ,basically 1/2 a DF in many ways . they rarely ran as single units . they probably lasted till the 80 's .
However , the next loco NZR brought was the american (and canadian ) da class . these were phemonally sucessful , and form then on it was all american , apart from the odd japanese loco .
If you google NZR DF class , DE class , and DG class you should come up with photos and info . Although there was a second DF class introduced in the 80''s , these were canadian , and stil in service .