Here are a few places to visit:
Beaton Institute - Cape Breton University beatoninstitute.com
The library at the university - microfilm machine
McConnell Library, Sydney - you can't print from their microfilm machine
Cape Breton Genealogy & Historical Association, Sydney cbgen.org
It's only open on Tuesdays and Thursdays (maybe more in the summer)
It's around $25 per year to join their web site. Whitney Pier Historical Society - I'm not sure if they would have anything on Glace
Bay but that is where the steel plant was located.
I hope this helps.