Shojo Beat is a magazine published in North America with the target audience of older teenage girls. SB was first publish back in June of 2005 but has since undergone quite a few changes. It now holds new features such as recipes, fashion tips, random articles and now has it's own panda mascot: Moko.
Similar to Shonen Jump, SB is a magazine that features manga by chapters and is out with a new volume every month. It also publishes the actual manga volumes as well which can probably be found at a book store near you. As series end and new series start, SB has gone through a number of series both in the magazine and seperately.
In the most current issues of SB, you will find the following series:
* Crimson Hero - by Mitsuba Takanashi
* Gaba Kawa by Rie Takada, premieres April 2008
* Haruka ~Beyond the Stream of Time~, by Toko Mizuno
* Honey and Clover, by Chika Umino
* Sand Chronicles, by Hinako Ashihara
* Vampire Knight, by Matsuri Hino
Some have started just recently while others have been around for a while. If you're just planning to pick up one, I recommend you read the summaries provided before each chapter.
The Giant List of Love
* Absolute Boyfriend (Zettai Kareshi) - by Yuu Watase
* Aishiteruze Baby (I Love Ya, Baby) - by Yoko Maki
* Baby and Me (Aka-chan to Boku) - by Marimo Ragawa
* Beauty is the Beast (Bijo ga Yaju) - by Tomo Matsumoto
* Beauty Pop - by Kiyoko Arai
* Crimson Hero (Beni-iro Hero) - by Mitsuba Takanashi
* Fall in Love Like a Comic! (Manga Mitaina Koishitai) - by Chitose Yagami
* Full Moon o Sagashite ("Searching for the Full Moon") - by Arina Tanemura
* Fushigi Yugi - Genbu Kaiden - by Yuu Watase
* The Gentleman's Alliance (Shinshi Domei Cross) - by Arina Tanemura
* Godchild (Hakushaku Cain) - by Kaori Yuki
* High School Debut (Koko Debut) - by Kazune Kawahara
* Kamikaze Girls (Shimotsuma Monogatari) - by Novala Takemoto (original novel) and Yukio Kanesada (art)
* Kaze Hikaru - by Taeko Watanabe
* La Corda D'Oro (Kin-iro no Corda) - by Yuki Kure
* Lovely Complex (Love*Com) - by Aya Nakahara
* MeruPuri (MeruPuri: The Märchen Prince) - by Matsuri Hino
* Millenium Snow (Sennen no Yuki) - by Bisco Hatori
* Monkey High! by Akira Shouko
* Nana - by Ai Yazawa
* Ouran High School Host Club (Oran Koko Host Club) - by Bisco Hatori
* Princess Knight (Ribbon no Kishi) - by Osamu Tezuka (an excerpt was published in the June 19th, 2007 issue of Shojo Beat)
* Punch! - by Rie Takada
* Special A (S.A.) - by Maki Minami
* Skip Beat! - by Yoshiki Nakamura
* Socrates in Love (Sekai no Chushin de, Ai wo Sakebu) - by Kyoichi Katayama (original novel) and Kazumi Kazui (art)
* Tail of the Moon (Tsuki no Shippo) - by Rinko Ueda
* Cain Saga (prequel of Godchild) - by Kaori Yuki
* Tokyo Boys & Girls (Tokyo Shonen Shojo) - by Miki Aihara
* Ultra Maniac - by Wataru Yoshizumi
* Vampire Knight - by Matsuri Hino
* Wild Ones (Arakure) - by Kiyo Fujiwara
* Yume-Kira: Dream Shoppe - by Aqua Mizuto
* Yurara (Yurara no Tsuki) - by Chika Shiomi
That there is a list of all the series that are attached to the SB name and have been gratefully published for our reading pleasure. Mostly all of these (if not every single one) are rated either T or T+ but they're all really good reads so you should pick them up or borrow one from a friend.