A fantastic online dictionary!
http://www.etymonline.com/
This website is the Purdue University online writing help lab. This site is
an excellent, reliable source of grammar, mechanics, and usage help.
http://owl.english.purdue.edu/owl/
The Merriam-Webster dictionary online...You can also try yourdictionary.com,
though of course, The Oxford (subscription required) is always the best!
http://www.m-w.com/home.htm
The same literary terms dictionary that is on my literature help page. One
of the best lists I've found on the web, since it offers examples and
accurate definitions.
http://www.virtualsalt.com/litterms.htm
This website also lists and defines literary terms, but each term is defined
by one of several students at UNC Pembroke--this group of definitions is
accurate and thorough, and sometimes a bit less dense than those on the site
above.
http://www.uncp.edu/home/canada/work/allam/general/glossary.htm
This website offers a good number of accurate, online texts.
http://www.bibliomania.com
A Literary timeline--the British and American time periods explained.
http://literaryexplorer.blondelibrarian.net/
A great, easy-to-use basic grammar help page, complete with definitions,
exercises, and handouts.
http://www.chompchomp.com
Another page with on-line literary texts.
http://www.bartleby.com
My favorite link to a Shakespeare glossary for finding the definitions to
those archaic words you don't know!
http://www.absoluteshakespeare.com/glossary/a.htm