Listmania!
Straussian's Guide to Wicked Nick
By an Amazon.com customer
The PrinceThe Prince by Niccolo Machiavelli
Buy new: $10.95 / Used from: $0.66
The first Straussian translation of The Prince, and still the most accurate.  Can be a clunky read, however.   Includes a fine introduction, and great explanatory notes.
The Prince: Second EditionThe Prince: Second Edition by Niccolo Machiavelli
Buy new: $10.00 / Used from: $0.98
Captures Nick's style and humor better than any other translation.  The introduction is a masterpiece of elegant economy.  The glossary added for the second edition alone makes this worth the price.
The Prince (Rethinking the Western Tradition)The Prince (Rethinking the Western Tradition) by Niccolo Machiavelli
Buy new: $14.00 / Used from: $1.48
Another Straussian translation of The Prince?  Yes!  This one comes with exhaustive word usage notes and four thoughtful essays.
Discourses on LivyDiscourses on Livy by Niccolo Machiavelli
Buy new: $16.80 / Used from: $11.11
Literal translation + dynamite intro + handsome design + lengthy glossary + mule's work of tracking down sources for every literary reference in the book = only edition worth considering.
Florentine Histories: (New translation) Introduction by Harvey Mansfield, Jr.Florentine Histories: (New translation) Introduction by Harvey Mansfield, Jr. by Niccolo Machiavelli
Buy new: $27.32 / Used from: $9.99
Machiavelli's diagnosis of the problems of his time.  Beautifully designed book, and the translation is up to the standards we expect from Mansfield.  Nick makes a cameo appearance in III 13.
Art of WarArt of War by Niccolo Machiavelli
Buy new: $16.50 / Used from: $10.40
Last of the "Big Four" to receive the Straussian translation treatment.  It's about time!  Read this and know that Nick was not a Renaissance humanist.
MandragolaMandragola by Niccolo Machiavelli
Buy new: $9.50 / Used from: $1.48
Most accurate edition of a play that, in only a few pages and with considerable humour, captures everything of importance in Nick's thought.  Lousy design, though.
CliziaClizia by Niccolo Machiavelli
Buy new: $10.50 / Used from: $1.00
Unfortunately overlooked play.  Even more outrageous than Mandragola.
Machiavelli and His Friends: Their Personal CorrespondenceMachiavelli and His Friends: Their Personal Correspondence by Niccolo Machiavelli
Buy used from: $19.50
Most comprehensive collection of Nick's letters.  You can skip the letters to Nick, but you MUST read the letters he wrote himself.
Machiavelli : The Chief Works and Others, Vol. 2Machiavelli : The Chief Works and Others, Vol. 2 by Nicollò di Bernado deiMachiavelli
Buy new: $27.95 / Used from: $12.95
Volume 2 is necessary for the Castruccio, but die hards will want all three.  Best English source there is for the "minor" works.
Thoughts on MachiavelliThoughts on Machiavelli by Leo Strauss
Buy new: $14.34 / Used from: $10.75
Hail to the King.  Bow down for you are not worthy.  The definitive interpretation.  Willmoore Kendall said it best: in trying to understand Nick, if you don't begin here, you are wasting your time.
Machiavelli's VirtueMachiavelli's Virtue by Harvey C. Mansfield
Buy new: $15.60 / Used from: $5.00
Great writing, great insights, great typesetting: who could ask for anything more?
Machiavelli's New Modes and Orders: A Study of the Discourses on LivyMachiavelli's New Modes and Orders: A Study of the Discourses on Livy by Harvey C. Mansfield
Buy new: $28.00 / Used from: $26.60
One of a kind.  Could be more forthcoming--but where else are you going to find detailed comments on EVERY chapter of the Discourses?
The Machiavellian Enterprise : A Commentary on the PrinceThe Machiavellian Enterprise : A Commentary on the Prince by Leo Paul S. De Alvarez
Buy used from: $29.99
Like "New Modes", this is the only book of its kind: a chapter-by-chapter commentary on The Prince.   Necessary if not sufficient.
Machiavelli's Three Romes: Religion, Human Liberty, and Politics ReformedMachiavelli's Three Romes: Religion, Human Liberty, and Politics Reformed by Vickie B. Sullivan
Buy new: $26.27 / Used from: $40.42
Let no one ever praise Nick for his "piety" again.
Machiavelli's RomansMachiavelli's Romans by J. Patrick Coby
Buy new: $87.00 / Used from: $36.95
"Anti-Straussian" reading of the Discourses.  Yet whereas most of Strauss's enemies either ignore him or caricature him, Coby is courageous enough to attempt to meet Strauss head on.
Well-Ordered LicenseWell-Ordered License by Markus Fischer
Buy used from: $242.50
Useful, especially the account of Nick's epistemology.  The argument that Nick bungled his way into modernity is not convincing, however.  And the book's design is embarrassingly amateurish.
The Comedy and Tragedy of Machiavelli: Essays on the Literary WorksThe Comedy and Tragedy of Machiavelli: Essays on the Literary Works
Buy new: $20.00 / Used from: $0.40
Would be good even without Mansfield's masterful essay on Mandragola.  Though in my opinion it loses its way as it becomes less and less Straussian.
Machiavelli, Hobbes, and the Formation of a Liberal Republicanism in EnglandMachiavelli, Hobbes, and the Formation of a Liberal Republicanism in England by Vickie B. Sullivan
Buy new: $110.00 / Used from: $74.99
Highly original.  Outlines the efforts of Nick's disciples to make the master's teachings more respectable.  The first chapter is the clearest short account of Nick's political science out there.
Machiavelli, Leonardo, and the Science of PowerMachiavelli, Leonardo, and the Science of Power by Roger D. Masters
Buy new: $24.95 / Used from: $21.00
Unique and wonderful.  Explores a much underappreciated aspect of Nick's thought.  Plus, pictures of monkeys!
Fortune Is a River : Leonardo Da Vinci and Niccolo Machiavelli's Magnificent Dream to Change the Course of Florentine HistoryFortune Is a River : Leonardo Da Vinci and Niccolo Machiavelli's Magnificent Dream to Change the Course of Florentine History by Roger D. Masters
Buy used from: $0.60
Too good to check?   Nonetheless, a delightful read.  Also the only book on this list light enough to take to the beach.
Machiavelli (Founders of Modern Political and Social Thought)Machiavelli (Founders of Modern Political and Social Thought) by Maurizio Viroli
Buy new: $55.00 / Used from: $23.82
Not Straussian at all; in fact Viroli is quite hostile to Strauss.  Yet chapter 3 masterfully shows how Nick appropriated and parodied classical rhetoric.
The Machiavellian CosmosThe Machiavellian Cosmos by Professor Anthony J. Parel
Buy new: $48.00 / Used from: $17.95
Explains the cosmology prevalent in Nick's time.  I think Parel is wrong to assert that Nick believed in it.  But he is right that understanding Nick requires understanding Renaissance cosmology.
The Education of Cyrus (Agora Editions)The Education of Cyrus (Agora Editions) by Xenophon
Buy new: $17.05 / Used from: $7.03
Straussian translation of Nick's favorite book.  Founding volume in the "Mirror of Princes" genre.  Machiavelli's Prince is part update, part refutation, of Xenophon's classic work.
Teach Yourself Italian Complete CourseTeach Yourself Italian Complete Course by Maurice Elston
Buy new: $15.56
Stop relying on the arms of others!