Although Aristotle's own writings are not easy to read, they reward deep study. Among translators of Aristotle, I much prefer Joe Sachs, who has rendered the Nicomachean Ethics and other key works into English. Unfortunately there is no great translation of the Eudemian Ethics, so I am planning to make one.
The best book I have read on Aristotle's philosophy of human affairs is Revaluing Ethics: Aristotle's Dialectical Pedagogy by Thomas W. Smith.
Several of the more approachable expositions are worth reading: Aristotle: A Very Short Introduction by Jonathan Barnes, Aristotle's Way by Edith Hall, Aristotle by John Herman Randall, In Pursuit of the Good by Eric Salem, and Aristotle's Ethics by J.O. Urmson.
The scholarly literature on Aristotle is vast; here I have found the following works especially valuable: Ethics with Aristotle by Sarah Broadie, Aristotle's Man by Stephen Clark, Bios Theoretikos by Trond Berg Eriksen, Action and Character According to Aristotle by Kevin Flannery, Confronting Aristotle's Ethics by Eugene Garver, The Aristotelian Ethics and Aristotle on the Perfect Life by Anthony Kenny, The Wisdom of Aristotle by Carlo Natali, Aristotelian Interpretations by Fran O'Rourke, Practices of Reason by C.D.C. Reeve, Taking Life Seriously by Frances Sparshott, and Aristotle on the Uses of Contemplation by Matthew D. Walker.
Complete Thyself is the final volume in a six-movement suite of books I'm writing on the art of living: