These are some sites that have Language Arts resources and helps.

General

National Council of Teachers of English (NCTE) Home Page. Professional Site.

NCTE Read, Write, Think. Collaboration between Marco Polo and NCTE.

The Children's Literature Webguide. Great site for book reviews and resources.

ProTeacher Community. Resources.

EduHound.com - Language Arts. 8 resources.

The Elements of Style. Online.

Dictionary/Thesaurus.com. As it sounds.

Library of Congress Information System. Find author, name or call number of any book in the U.S.

MightyBooks.com. Free read aloud picture books, video song books, and more!

Specific

The Complete Works of William Shakespeare. All things Shakespeare.

The Encyclopedia Mythica. A mythology, folklore, and more online encyclopedia.

High School Journalism. Links and information for secondary journalism teachers.

Plagiarism Workshop. Directed towards HS students.

Exhaustive Lists of Sites.

CanTeach Links - English Language Arts. Great list of resources divided by topic.