Ellen Hopkins' "Kristina" books are the books that not only got me into YA but got me loving books in verse. I'll be forever grateful because before reading her books I would have never guessed I'd fall in love with either one.
Glass, Crank, and Fallout (the Kristina books) are by far my favorites. I've loved her others as well. I'd urge anyone to at least try one of her books. Even if you're not into the genre, not into verse, think about giving it a try - they're fantastic.