The Gangster's Guide to Diction

 is a cassette tape in Wasteland 3.

Description
This cassette is labeled only a drawing of a man wearing a mafia outfit. The text says, "Cool guy."

Transcript
So, youse is a discerning gennlemans, whose wants ta learn how to talk like the toughest wise guys dat eer was? Well, congrats, jabroni, youse has come to da right tape. Ey, wassamatta? You wanna join da outfit but you ain't got da lingo? Well, congrats, jabroni, 'cause you come ta da right tape. Da Gangster's Guide ta Diction got everything ya need ta know! It don't matter if you're a bag man or a button man, we'll have ya talkin' like a made man in no time! So grab a cannoli and pull up a chair, and let's get ya mobbed up.

Locations

 * Little Vegas: In the backrooms, inside a locker.