what should i watch next?

Horror

-Another
-Le Protrait de Petit Cossette ((3EPS))
-Elfen Lied
-Death Note
-Deadman Wonderland

Shoujo

-Kimi ni Todoke
-Ouran High School Host Club
-Ano Natsu no Matteru
-La Corda d'oro
-Skip Beat
-Vampire Knight
-Eden of the East
-Angel Beats
-Hakuouki
-Natsuyuki Rendevzous
-Uta no Prince-sama
-Otome Youkai ZAkuro

Shounen

-Naruto/Shippuden
-Bleach
-Kuroshitsuji
-Durarara!!
-InuYasha
-Kuroko no Basket
-GetBackers

Other

-WAGNARIA!!/WORKING!! ((shounen/shoujo))
-Summer Wars ((MOVIE))

Well just from Hell Girl it doesnt give me a whole lot to go on but here goes..

*Darker Than Black
*Death Note
*Blue Exorcist
*Mushi-Shi
*Angel Beats
*Nabari no Ou
*Red Garden
*Ghost Hound
*Ghost Hunt
* Pet 商店 of Horrors (only 4 eps)
good luck ;)

你 should watch Angelic Layer! Im watching it right now on Youtube! Its fantastic and its in English sub 或者 dub.
Its based off a 日本漫画 series 由 CLAMP!

Well, 你 can try some of these:

- Soul Eater
- Death Note
- Shaman King
- Fullmetal Alchemist/Fullmetal Alchemist Brotherhood
- Blood +/Blood C
- 天使 Beats
- Higurashi
- Katekyo Hitman REBORN!
- K Project
- Naruto/Naruto Shippuden
- One Piece
- Bleach
- Fairy Tail
- Hetalia
- K-ON!
- Another
- Anything from the "Tales of..." series (I liked The Abyss)
- REC
- Starry Sky
- Fruits Basket
- Pandora Hearts
- Clannad
- 杜松子酒 Tama
- 《黑执事》 (Black Butler in English)
- Danshi Koukousei no Nichijou

And many, many more. These are just some of the 流行的 ones. And they are pretty awesome starter 日本动漫 (mine was Naruto). 你 might wanna watch some classics, too. Like Sailor Moon 或者 Dragon Ball Z, to set a example