My definition of 'folk' - to me, means what people are singing and listenting to! Allso these are all easy since I'm just trying to pick up guitar again after a 45 year break :) .
Ccr, Bob Dylan, Kingston Trio, Woody Guthrie, Beatles and Creedence Clearwater Revival
Variety of genres
Grateful Dead, Leonard Cohen, Jackie Wilson, Groucho Marx, Bob Marley and Gerry Rafferty
Easy Guitar Playing 2
Neil Young, Blue Rodeo, Band, Neil Diamond, By The Eagles and Monkees
Stuff that I like
Folk blusey stuff; some traditional, S&G, Judy Collins, Joan Baez, Dylan, etc.