I was reading
this thread and I agree that it is all about the right keywords.
Since I run a site in different languages I am struggling to find the right keywords. For instance I was looking into Wordtracker, but after doing some research I found out that they don't have any other languages than English yet.
I have been trying different tools, but at the moment I don't know any but my common sense and the Google Keyword Tool
Which tools do you use?