obviously all the stevie wonder 70s lps up to songs in the key of life are essential, as are the 70s isley brothers albums, but if you only get one from each, then get innervisions and 3+3. also get donny hathaways live album - most of his albums are patchy and even this one is a bit hit and miss too, but its probably his best album overall, has great covers (lennons jealous guy and whats going on, which when i first heard it, thought it was as good as marvin gayes, but now im less enthusiastic about that). also get aretha's young gifted and black, which has rocksteady. everyone goes on about her 60s stuff as its canonical but she was still making great stuff in the 70s. also get marvin gayes i want you and here my dear. less famous stuff you could get - shuggie otis' inspiration information, curtis' sweet exorcist, graham central stations first album (more on the funk side but larry graham was a really good songwriter, albeit very sly-sounding, in the beginning), labelles nightbirds album (produced by allan toussaint, whose album with southern nights from a whisper to a scream is worth finding - hes not the most arresting vocalist but the songwriting is really strong) or chameleon, minnie riperton's perfect angel and syreeta's stevie wonder presents syreeta (both produced by stevie), roberta flack's killing me softly, also EWF's stuff is pretty essential - thats the way of the world, gratitude (cant hide me love is brilliant), or spirit are all worth getting.... theres loads of stuff you could get really. hopefully i mentioned some stuff that hasnt been said already. ive listed 70s soul really, just cos thats my favourite period, and when i think it matured, but theres tons of good 60s stuff too.