IELTS
http://www.testpreppractice.net/
English Language Sources (Research Links with tips)
http://www.thefreedictionary.com/
http://www.englishlanguageguide.com/
http://www.english-online.org.uk/
http://etext.virginia.edu/collections/languages/english/
http://www.englishclub.com/english-language-history.htm
http://www.englishforum.com/00/interactive/
http://www.britannica.com/EBchecked/topic/188048/English-language
LISTENING SKILLS SITES
http://www.englishlistening.com/
RADIO STATIONS for Listening
http://www.zozanga.com/internetstuff/englishradiostations.htm
WRITING SKILLS
http://grammar.ccc.commnet.edu/grammar/
READING SKILLS
http://eslus.com/LESSONS/READING/READ.HTM
http://freelanguage.org/learn-english/skill-enhancement/improve-english-reading-skills
http://www.eslmonkeys.com/student/storyroom/storyroom.html
SPEAKING SKILLS
http://www.learnenglish.de/improvepage.htm
http://www.ericdigests.org/2000-3/adult.htm
http://www.englishclub.com/speaking/language-skills.htm
http://www.english-at-home.com/speaking/better-english-speaking-skills/
http://www.splendid-speaking.com/
ADVANCED ENGLISH GRAMMAR LINKS
http://www.englishpage.com/verbpage/verbtenseintro.html
http://www.englishpage.com/gerunds/index.htm
http://www.englishpage.com/modals/modalintro.html
http://www.englishpage.com/prepositions/prepositions.html
http://www.englishpage.com/vocabulary/vocabulary.html
http://www.englishpage.com/modals/interactivemodal5.htm
LINGUISTICS ENCYCLOPEDIA LINKS
http://www.routledge-ny.com/ref/linguistics/
http://www.encyclopedia.com/topic/linguistics.aspx
http://www.sciencedirect.com/science/referenceworks/9780080448541