Hello, I have just started researching John Allison. I got interested in him and his paintings when I came across the March 25, 2018 offerings through the Butterscotch Auction Gallery.   I believe you can still access the link online.   They offered approximately 30 lots, including artwork, a collection of his albums as well as his personal victor gramophone, and some personal items. I did manage to win a few lots including a file of writing and photos, which I hope to receive in the coming weeks. It is curious they use Williams as his middle name, but my research indicates Blauvelt is/was his middle name as indicated in an earlier post.   I found an article entitled "John Allison- The Collector as Folk Artist". Published by New York Folklore Vol 9 Issue 3 (1983) pages 27-36. It is copyright protected and as such I cannot post it here. It can be purchased for $3 and I found it very informative, well worth reading.   You can access the link and see a preview for free.   

I am still searching for other information but to date have not found much...either in the way of obituary or other documents. It appears John died October 1, 1981.. I did find through the 1920 and 1930 census he had two children, John D born 1934 and Joan born 1927. I hope to have more to post after I do a bit more research. I welcome any other information that might com to light.