I had a 10 year-old boy come to the information desk today asking for Robert Jordan's Wheel of Time and books by Terry Goodkind. His father said his favourite books so far were the Lord of the Rings series and that he was looking for more epic fantasy. As I searched the catalogue his father picked up a book from the Vampire Diaries series and commented, "Hey look -- you like vampires -- maybe you'll like this!" Yikes! I had to quickly warn him that this series was quite different from classic epic fantasy and that these vampires weren't the same as the Dracula found in Stoker's work. The boy told his father that Vampire Diaries was a TV show and promptly put it back on the shelf.
I then racked my brain for possible YA and children's titles that included vampires -- real scary, bloodsucking ones -- and could only come up with one or two (e.g.  Department 19 by Will Hill, Alex Van Helsing: Vampire Rising series by Jason Henderson).
Most of the other children's and YA novels featured vampires exploring their self identity, falling in love with humans or other supernatural beings (e.g. Evernight by Claudia Gray), as vulnerable beings venturing out into our world (e.g. Morganville Vampire series), as part of the regular paranormal society (e.g. Araminta Spooky Series by Angie Sage) or were parodies (e.g. Bunnicula series by James Howe, The Reformed Vampire Support Group by Catherine Jinks). Not really material that would appeal to a reader looking for something truly creepy and frightening. And definitely not material for someone looking for epic fantasy.
It was hard to find the more serious, traditional YA fantasy amidst all the new (YA) paranormal fiction (he didn't want anything from the children's fiction), and I did end up bringing him to the adult section where he appeared much happier with the options. I've love to see more of that classic fantasy published for young adults -- stuff following the traditions of Yolen, Tolkien, C.S. Lewis and the like. While some may claim such stories are too dense and long for kids, I think we'd be surprised to find that there is an audience just waiting for this sort of thing.