Many theologians/philosohers wrote commentaries on Peter Lombard's Sentences. Aquinas' commentary is available on Logos as well as a few others.
Yet the actual writing of Peter Lombard's Sentences (as far as I can see) is. It available in Logos.
I posted on UserVoice a very neat 4 volume translation. Would love to see it gain some traction!
https://suggestbooks.uservoice.com/forums/308269-book-suggestions/suggestions/31322191-peter-lombard-sentences-vol-1-4