Style

Dictionary of English: Clichés, Pretentious Language, and Jargon - Presents a list of examples of three kinds of language to avoid, with an explanation of why they are not recommended.
http://www.tiscali.co.uk/reference/dictionaries/english/data/d0081759.html

Grammar Slammer - This help file indexes style and usage, capitalization, abbreviations, punctuation, letter writing, common mistakes and a grammar glossary.
http://englishplus.com/grammar/index.htm

Garbl's Editorial Style Manual - Searchable advice on abbreviations, capitalization, grammar, numbers, punctuation, spelling and word usage.
http://home.comcast.net/~garbl/stylemanual/

New Words In English - Neologisms and new uses of words in English.
http://www.owlnet.rice.edu/~ling215/NewWords/

Top20Composition.com - Online directory for grammar, spelling, puncuation, research, creative writing, and proofreading resources.
http://www.top20composition.com

Common Errors in English - An explanation of common English usage errors and how to avoid making them.
http://www.wsu.edu/~brians/errors/

The Sports Cliche List - A searchable collection of cliches used by American teams, fans, coaches and commentators, with humorous comments and sound clips.
http://www.sportscliche.com

The Elements of Style - William Strunk - Principal requirements of plain English style. Focuses on the rules of usage in literature, composition and grammar.
http://bartleby.com/141/

AmeriSpeak - Common American sayings and what they actually mean.
http://www.rootsweb.ancestry.com/~genepool/amerispeak.htm

WordWizard - Learn about word meanings, slang, quotations, insults, and famous authors.
http://www.wordwizard.com/

Plain English Campaign - Working internationally to try to get public information written in plain English, instead of using gobbledygook, jargon and legalese. Includes examples, with annual awards for the worst offenders.
http://www.plainenglish.co.uk/

AskOxford.com - For questions on English grammar, spelling, and usage. Search a dictionary of words, names or quotations.
http://www.askoxford.com/

Plain Language - A guide to help writers avoid confusing language and long-windedness. Can be viewed online or downloaded as a PDF.
http://www.plainlanguage.gov/

Cliché Day Quiz - Test your knowledge of the origins of common cliches.
http://reference.aol.com/quizzes/cliche-day

Guide to Grammar and Writing - Features searchable index of grammatical rules, explanations, comments on style, and usage suggestions.
http://grammar.ccc.commnet.edu/grammar

Cliche Finder - A searchable database of overused expressions, with a fun feature creating a random list.
http://www.westegg.com/cliche/

What is Plagiarism? - Answers common questions that students may have on the subject and confronts some of their excuses for not giving proper credit to their sources.
http://www11.georgetown.edu/programs/gervase/hc/plagiarism.html

Capitalizing - Provides a list of rules and examples. Includes sentences, quotations, proper nouns, names, titles, and scientific nomenclature.
http://englishplus.com/grammar/captcont.htm

Right Words - A series of short articles about grammar and punctuation, with light hearted examples of common mistakes.
http://rightwords.co.nz/index.php?option=com_content&task=category&sectionid=4&id=13&Itemid=30