Um, "novella" might be the term that you guys are looking for, although "Harrison Bergeron" is definitely a short story. For whatever reason, it's on the reading list for a lot of Grade 9 curricula: we had to read it as well.
Vonnegut is more or less my second favourite novelist after Henry Miller. I started reading his stuff when I was thirteen or so, and haven't looked back.
"The Sirens Of Titan" is my favourite Vonnegut book. It just seemed to sum up all of my feelings about people, the world, etc., at the time.
Other good ones: "Mother Night" (there was a pretty decent movie adaption starring Nick Nolte), "Breakfast Of Champions" (there was a bloody awful movie adaption starring Bruce Willis), "Timequake", "Wampeters, Foma, & Grandfalloons".
His short story material is somewhat hit and miss. The earlier stuff was more or less quick fodder for the dozens of fiction magazines that were hugely popular in the USA in the '50s. Vonnegut himself has admitted that it's not his best work, and that he was more or less just churning it out to make a living. There are a few decent ones, though.
I've been meaning to write him a letter for the past seven years, and have yet to do so. I'm terrified that he will die before I write to him, yet conversely, I'm terrified that if I do write to him, he'll die as soon as I mail the letter, as if some strange universal force was telling me, "See? You
should've written him earlier."
Maybe I should just write to Kilgore Trout.
Yeah...