To begin with, St. Patrick's Day, as celebrated here in the U.S. is the most racist holiday out there. Everyone eats corned beef and cabbage (yuck!), a meal rarely seen in Ireland. Green beer flows endlessly, both in and out of people who look at St. Patrick's as a reason to get so drunk they will call in sick the next day. Cheap green hats abound. Everyone wears green to avoid being pinched. Every cheapass tenor thinks they can sing Johnny Boy, I'll Take You Home Again, Kathleen (especially the Star Trek Fans), Mother Machree or some other tired old pub song. If you get really lucky you might hear an Irish band play a good version of Whiskey in the Jar. Everyone will wear a stupid "Kiss Me I'm Irish!" button. And for one day out of the year, red hair is really popular.
Book of Kells and blank looks are all you will get. Mention the Book of Lindisfarne and again blank looks. If you mention gaelic, especially in conservative neighborhood, you begin an argument over traditional marriage. You are likely to be somewhat safe in referring to The Quiet Man or maybe Enya, but never hope to mention a film based on Roddy Doyle's books (I dare you, there are three, name one without looking it up).
If it seems weird that I should be complaining about all the stereotypes, ask yourself how you celebrate St. Patrick's Day. What do you do to celebrate Ireland? Do you watch a film with your favorite Irish actor? If not I would suggest just about any film with Brendan Gleason (yes, even Lake Placid), though most especially The Guard. If you want to listen to some Irish music, may I suggest:
I am just saying put down the fucking mint shake from McDonald's for moment and try to think of something Irish. Look up a bit of history, or artwork, or learn which authors are Irish (Arthur Conan Doyle and Bram Stoker are two). Even if all you do is try to figure out what it is that Brad Pitt is saying in Snatch, at least that is a more honest celebration of St. Patrick's Day than eating something with green food dye.