Thank you Mr. Param. I really appreciate your help. However, I had indeed come across this pdf before, and I must mention that this one seems to have been created based on Wikipedia itself. I found this on the Internet Archive (
https://archive.org/details/FilmfareAwards) and it was uploaded by user kailash29792 on 24 February 2016, who also happens to be a Wikipedia editor (
https://en.wikipedia.org/wiki/User:Kailash29792).
This list also has its share of discrepancies. For example, it mentions that Anuradha Paudwal was nominated at the 35th Filmfare Awards held in 1990 for Ram Lakhan, but doesn't mention for which particular song was her work recognised (she had sung 3 songs for the film). And yes, I am more interested with the nominees since winners have been widely documented by several writers. Even a simple Google books search provides links to free previews of many books which list the winners in various categories as well as for the special awards.