@Medlinniel on Twitter asked for recommendations; here's what she likes: "Vampire Diaries. Pretty Little Liars.. True Blood and... The New Girl (which isn't out yet)"
Okay! First of all, if you like Vampire Diaries, you must try The Secret Circle. It's made by the same people, and based on another trilogy by the same author. It's about a young girl who moved to a small seaside town to live with her grandmother and discovers that her family is one of several families of witches in the town. I've seen the pilot and liked it a lot. For your viewing convenience, it's on the CW on Thursdays at nine, right after Vampire Diaries.
You should probably try the CW's other new show Ringer, on Tuesdays at nine. It stars Buffy's Sarah Michelle Gellar and just cast Moonlight's Jason Dohring (also known as Logan from Veronica Mars), so it's sort of vampire-adjacent. It's about a woman on the run who tries to stay safe by impersonating her missing, estranged twin sister, only to discover that people are after the twin as well. It doesn't look like it's going to have a supernatural element, but the pilot has a similar feel to the sort of shows it sounds like you like - somewhere between PLL and Nikita with a little Gossip Girl thrown in.
A few more ideas: ABC's Revenge is a Hamptons soap about a young woman trying to get revenge on the rich community that somehow ruined her family, and it looks like it could be a lot of fun. (It's loosely based on The Count of Monte Cristo. And if you're looking for more shows with magic or supernatural elements, try ABC's Once Upon a Time and NBC's Grimm.
I hope that helped! If you try any of these shows, let me know what you think!