I am trying to do niche marketing recently and keyword research is probably the most important. I have been using Keyword Elite and some free keyword tools like Google Adwords Keyword Tool, Free Wordtracker tool and SEObook tool. However, I am not really sure how to do the keyword research. I just know that I have to find a main keyword and many long tail keywords that have hign demand and low supply. But I really have a lot of problems with that. So anyone here can help me?