Don't know about getting a celeb drunk deliberately but there have been some hillarious cases where a celeb has turned up drunk. My favourite is Olly Reid On "After Dark", there where a bunch of lefties having a deep and meaningful discussion about organic peace vegitables or something and in walks Ollie with a jug of screwdriver and proceeds to try an cuddle one of the "Wimmin", wonderful!
Then of course who can forget George Best on Wogan? Even Tracy Emin was ratted on some talk show or other.