These fivelinks have a lot of resources for different skills. These are five ofmy favorite links:
http://www.aitech.ac.jp/~iteslj/links/
http://www.tc.umn.edu/~babin005/esl/index.htm
http://clinique-edouard-rist.scola.ac-paris.fr/f_abstudents_corner.htm
http://longman.com/cws/index.html
http://www.beaumont-publishing.com/efl/links.htm#magazines2
http://www.literacynet.org/cnnsf/archives.html
http://lc.byuh.edu/CNN_N/CNN-N.html
http://members.juara.com/abelardo/reading/reading_comp1.html
http://lc.byuh.edu/CNN_N/CNN-N.html
http://college.hmco.com/esl/mahnke/grammar_links3/1e/students/ace_v2/index.html
http://www.eslpartyland.com/teachers/nov/grammar.htm
http://www.lclark.edu/~krauss/toppicks/grammar.html
http://www.buckhoff.topcities.com/adjective_clauses.htm#Reduced adjective clauses:Quiz 3
www.abcnews.com (Watch and read!)
http://eleaston.com/listen.html
http://www.ohiou.edu/esl/english/writing/activities.html
http://www.gsu.edu/~wwwrtp/topics.htm
GRE