Ok, I’m just wondering… How the heck do you use antidiestablishmentarianism, floccinaucinihilipilification, and pneumonoultramicroscopicsilicovolcanoconiosis (I’m not sure i spelled those rite) in a sentence. I was also wondering the pronunciation of them. If you can help I’ll be happy! Thanks! 
Welcome to the Straight Dope. Just so you know for the future, it’s helpful to put in a link to the column in question so that everybody is talking about the same thing from the beginning. You put the question in the right forum, though, and that’s a superior start.
The column is What does antidisestablishmentarianism mean?
Pronunciations are hard to set down in text, but it helps to break down these long words into their component parts. Think anti-dis-estab-lish-ment-arian-ism, flocci-nauci-ni-hili-pili-fi-ca-tion, and pneu-mo-no-ultra-micro-scopic-silico-volcano-co-niosis. See? Each is just a compound word built up from many smaller and more ordinary words. Well, not floccinaucinihilipilification, but that’s because it was invented as a nonsense word out of nonsense syllables just to be a long word.
None of them ever really get used in sentences except ones like the preceding: sentences talking about long words. If you’re a specialist in certain areas - church history or lung diseases - you might have a need to apply these words for a specialist audience. Otherwise, forget it. They’re like certain celebrities - known for being well known and nothing more.
Heh. My spell checker just spit at me. 
Hey thanks for helping me now i can be the only person who knows how to pronounce it where I come from
“Pneumonoultramicroscopicsilicovolcanoconiosis” is a 20th-century fraud, and “hippopotomonstrosesquipidelian” is fake, too, but all the bits of “floccinaucinihilipilification” up to “-ification” are legitimate Latin, although the word was always intended to be more or less a joke.
As far as I know, outside of science, “antidisestablishmentarianism” is still the longest English word that was not invented as a joke, but simply came up because someone needed it.
“The government is full of socialists and their antidisestablismentarianism makes me retch.”
It doesn’t count (words for chemical compounds can be slung together to any arbitrary length) but just out of interest Quinion has a whopper of 1,913 letters on his site. It’s the full name for tryptophan synthetase, a protein, which has 267 amino acids in it.
The staff report linked in post #2 also mentioned a “full name of the tryptophan synthetase A protein, an enzyme with 267 amino acids, extends to 1,913 letters”. Co-incidence? You be the judge!
I believe this question is its own answer.
After his pneumonoultramicroscopicsilicovolcanoconiosis was miraculously cured, Arthur became very religious and his antidisestablishmentarianism was so extreme that he viewed all arguments to the contrary as floccinaucinihilipilification.
A nice word for those who like to pepper their speech and writing with inordinately long words - sesquipedalianist.
And, as Quinion says, “there’s always hyperpolysyllabicsesquipedalianist for someone who enjoys using really long words.”
The answer to this one is simple; I don’t use words like that in a sentence
I actually have used “antidisestablishmentarianism”. It does fit in when discussing church-state relations in England.
Actually I don’t really get “antidisestablishmentarian”. Why don’t the “anti” and the “dis” cancel each other out and leave “establishmentarian”? You’ve got the disestablishmentarians, who want to disestablish the Church of England, and the establishmentarians who want to keep the Church of England as the established church.
Personally, as a strong support of the separation of church and state, I’m a contra-antidisestablishmentarian.
First there were the establishmentarians, who wanted to establish the C of E. Then came the Catholic monarchy under Mary Tudor, who wanted to dis-establish the C of E. Then came Elizabeth, who un-dis-established the C of E, also known as re-establishing. So the present movement to dis the C of E should be the contra-un-dis-establishmentarians, and those opposed to them would technically be the anti-contra-un-disestablishmentarians.
The quasi-establishmentarians and the pseudo-disestablishmentarians are discussed more thoroughly in the appendix.
That simply isn’t the way language works in the real world, especially considering that the Establishment has been around uninterruptedly since the Restoration.