There's certain American dialects that add an R at the end of a word, too. "Pizzer" (instead of pizza), "Winder" (Instead of window). It's mostly those from the south that say it that way.
In the case of "extraordinary', most people pronounce it "extrordinary" but, actually, each pronunciation has a slightly different meaning. The above example means: odd, bizarre, amazing, etc.. But, to say it, "extraordinary" means: to go the extra steps, to be something special, wonderful or, again, amazing.