[kramarao]

There are couple of books by Leo Rosten, Joy of Yiddish and Joy of Yinglish, that teaches Yiddish words through jokes and anecdotes. It used be my bedside reading for an year! Once you learn Yiddish words and the phrases, the sitcom dialogues started making more sense (like "from your lips to God's ears" or such turn of phrase).

[panglott]

Michael Chabon's essay "A Yiddish Pale Fire", which discusses his encounter with a Yiddish travel guidebook that eventually inspired "The Yiddish Policeman's Union", is a great read too, if you can track it down. Looks like it's disappeared from the Web.