She's a legendary figure here in WV, for good reason.

Her autobiography is here at the Digital Library. It's got a lot of details about her earlier life as an Irish immigrant. You can see why she would be eventually motivated to adopt the coal miners: she'd lost pretty much everything else - her family, her business.

A pretty good bio is Dale Featherly's Mother Jones:The Miner's Angel ( Carbondale: Univ. of Illinois Press, 1974) Elliot Gorn's newer Mother Jones I have not read, but it has gotten good reviews, like this one. I suspect that it takes a more sober, less admiring approach to the labor battles she fought.