Yeah, Google Adwords is the best tool for keyword research. It will do all the task for you. You can get most relevant keywords as per your region and category. Right keywords will take you to the doors of success.
of courde how to choose a good keyword is very important!
The very first thing that you should consider when going to choose keywords to target for your site, is the commercial intent for those keywords. By this it mean are an individual who write this keyword into Google search box in a buying mode or just getting information.