Read up on Perry Marshall, he seems to be the go to source for all of it. Additionally, Trada.com is providing a crowd-sourced solution. Tools wise I guess I

Read up on Perry Marshall, he seems to be the go to source for all of it. Additionally, Trada.com is providing a crowd-sourced solution. Tools wise I guess I would refer you to wordtracker, and other keyword research tools. Since the more specific you are with your terms the lower the bid price can be.