Talktomeinkorean is my personal fav

Very helpful sites from all of you.

http://www.koreanwikiproject.com/wiki/Main_Page  

 ---is very good for learning 한글 (Hangul - the Korean alphabet).

http://langintro.com/kintro/index.htm

http://rki.kbs.co.kr/learn_korean/lessons/e_index.htm

http://hompi.sogang.ac.kr/korean/

and www.talktomeinkorean.com

Good Luck!!!

Thanks very much. I will accept your advice and I think I will learn more Korean.

The textbook that we used in language training school is 首尔大学韩国语. 

http://kr.hujiang.com/new/p438176/

http://kr.hujiang.com/