Jim, Mike and I have been on a similar quest and have started to catalog our accumulated hoard... I intend to donate the majority to the Blunt Library at Mystic Seaport Museum so it will be available to any interested, since they will have a nautical or maritime component and there is the shanty singing program there... here is the link to what is in their collection so far:

https://research.mysticseaport.org/info/ib93-2/

most of their wish list will be filled by our donation this spring along with others not mentioned.

I am also working on compiling a lost of websites that provide access to songs... but this is slow going for me

I'm still trying to figure out the best home for my copy of Creighton's Gaelic Songs in Nova Scotia since there's only a few maritime ones in the printed collection which feature the old tongue and translations by Calum MacLeod. It's a bt disheartening at how many we've found came as library discards... so the right home is critical if it's to remain available for new folks that don't have tons of money to spend on books