Other web resources

Paul Brians' Common Errors in English Usage provides detailed and accurate explanations of the most common errors seen in writing. One of the treasures not to be missed is the section on non-errors. Feel free to use this site to disabuse your persnickety want-to-be English teachers who insist that you shouldn't split your infinitives or end your sentences with a preposition. They're just wrong. Actual English teachers tend to be more pragmatic.
Penguin Brief Handbook is an excellent source for grammar explanations and exercises for both native and non-native English speakers.

The Council of Writing Program Administrators' statement on plagiarism and the mutual responsibility that faculty and students share in avoiding it.

Visit Re: Writing for grammar assistance, to learn how to properly cite sources, for hints on avoiding plagiarism, and more. This one website can help you with all stages of the writing process, from thesis statement to bibliography.
The Purdue University Online Writing Lab features more than 100 handouts on a variety of subjects from audience analysis to using semicolons correctly.
Writer's Handbook is the University of Wisconsin's writing website. It contains information on writing research papers, science essays, application materials, and analytical literary papers.

Bedford St. Martin's Online Style Guide is a reference for MLA, APA, Chicago, and CBE citation styles, including internet source sitation styles.
Diana Hacker.com is one of the best on-line sites for documenting sources in MLA, APA, CBE, and Chicago style. There are also good sample essays and grammar exercises available.

Merrian-Webster's Dictionary This on-line dictionary site finds definitions for input words and contains a very effective online thesaurus.

Business Correspondence: Overview is a guide to the general format of business letters, discussing basic guidelines and basic business letter formats.