The one effective way to choose the best keywords for your website is to think about what your potential customers would type in if they were looking for you, your product or your service.
Sometimes your creativity requires a little boos t .Wordtracker, the Overture Search Term Suggestion Tool and the Google AdWords Keyword Tool can be that little boost. These tools will help you to find which search terms web surfers are using.
Overture Search Term Suggestion Tool
Google AdWords Keyword Tool
The Digital Point Keyword Suggestion Tool is a front-end that combines both the Wordtracker and Overture Search Term Suggestion Tool.
NicheBot combines Wordtracker results with page counts from Google, so that it can create a ratio which represents keyword competitiveness.
The Overture Keyword Popularity Tool is a front end for the Overture Search Term Suggestion Tool which is easier to use and creates a good chart of statistics.
The Free Google Suggest Tool is a front-end for Google Suggest that expands its reporting capabilities.
Good Keywords is a free application for Microsoft Windows which is designed to find the perfect set of keywords for your web pages.
So, I hope these tools will definitely help you to choose the best keywords.