This slide show explains essential questions.
This site provides useful tips for creating a list of key words you can use in your research.
The first step of your research process is defining your task. You will need to figure out:
*What is my essential question?
*What are two questions related to my essential question?
*What are keywords related to my questions that can be used to search resources for information related to my topic?
This page contains resources that can help you arrive at these answers.
This wiki presents a good way to get started developing good questions.