Includes background on the opera (and its history at the Met), a synopsis, a full libretto with English translation, photos from multiple productions, and endnotes.
Because this guide seems to be geared toward opera singers (many of the endnotes deal with Italian vocabulary), the libretto is translated word-for-word below the original, then retranslated below in parentheses for those passages where the grammar really doesn’t make sense.
Therefore, this isn’t a first choice if you want a literate, rather than a literal, translation. On the other hand, the endnotes point out all the sexual puns, so there’s that.