Does anyone know of any references to Shakespeare, translations of his works, or anything related to Shakespeare in classic Rabbinic sources?
I don't know if this qualifies as a truly "classic" source, but there is a classic essay by R' Zevin about "The Judgment of Shylock According to Halachah."
Update: It seems that Hebrewbooks has removed this sefer (לאור ההלכה) from their collection. I could not locate the article anywhere else online, except for a snippet view in Google Books here. Also of likely interest are two articles discussing that essay: 1, 2.