NATCECT never has any money, so I should think the prospects of any of the material in their archive being made freely available on the net, or anywhere else, are pretty much zero; except where a particular project like the Traditional Drama Research Group has transcribed documents. Such resources as they have (there isn't even a full-time archivist any more) are better devoted to conservation of the materials than in giving us something for nothing.

The Hudlestone book isn't especially easy to get hold of (see above) as you have to order it from the contract publisher, and the fact that it's ring-bound means that mainstream booksellers won't stock it. That's a pity, and so is the price; but we can't have everything. Apart from Frank Kidson's work (his Traditional Tunes can be got as a facsimile paperback from  Llanerch Press), Steve Gardham's East Riding Songster is still available, though you probably have to get it direct from him. Other than that, the fairly extensive collection made in the early 20th century in South Yorkshire by R.A.A. Gatty is kept at Birmingham Reference Library; very little of the material has ever been published.

To an extent, I'd guess that logistics have been something of a disincentive to collectors, particularly in the North of the county, where geography and demographics would have made the exercise especially difficult. The point made (I think by Georgina Boyes?) that [many] collectors didn't expect to find much in urban areas is true, but far from being the only factor. The advance writeup for the radio programme was rather misleading in its implication that the Hudlestone collection is the only one, though it is certainly important.

I think that James Madison Carpenter collected in Yorkshire in the '30s (along with many other places), but the search routine at the online catalogue seems to be broken, so I can't check. He had a car, though; earlier collectors had to rely mainly on trains and bicycles to get about. His collection probably will be available online eventually, but there are complicated legal permissions to be sorted out first. That project is American-funded, so at least there is money available.