Here are also some sites that you might like to check, they could help you practice grammar as well as vocabulary ,comprehension and pronunciation in English. Lots of quizzes and tests as well to test your level. They are supported with audio and video material :
www.learn-english-online.org/
www.1-language.com/
www.1-language.com/audiocourse/index.htm
www.learnenglish.de/
www.ego4u.com/
LatitudeU.com/
www.Englishtown.com/
www.usingenglish.com/testing.html
www.usingenglish.com/quizzes/
eleaston.com/quizzes.html
Good luck:)*