I really liked reading the reissue of L.J. Smith's Vampire Diaries, so I am super excited to know that (a) she is writing a fifth book, Vampire Diaries V: Damon, and (b) her Nightworld series is going to be similarly reissued. Yay! Read about it all on her website.
Also, I have really liked Mari Mancussi ever since The Great Sartorial Debate™, and I finally read Boys That Bite. We buy pretty much every YA vampire book published since the teens can't get enough, and I usually end up reading them too. Unless your students/teen patrons are not like this, I suggest getting Boys That Bite. It's light, breezy, "chic lit" vampire stuff with lots of pop culture slang and references, but it's a really easy read and very fun. I haven't liked a lot of vampire books since Twilight, despite my best efforts (ie. reading every one published), but this one was, while not the deepest or certainly scariest book, easy to get into and an enjoyable to read.