L.S.
Ancestry.com by far gives you the most bang for your buck so to speak. Many libraries with genealogy departments have Ancestry. com that you can access for free. They would probably also have Heritage Quest which is free to use at the library. Another free site is Family Search.com which has lots of genealogy information and you can access this from your home. It is best to start with the most recent information and work back. And also don't forget to look for the other family members which may give you clues to further your research.
I would recommend that you start with your local library and genealogy society and see what they have and try out the sites to find the one you like and works for you. I have been doing genealogy for over ten years and must warn you that it can become very addictive. Good luck and happy hunting.
Be sure to document all the resources you use and where you found the information so that in a couple of years you will be able to go back and see and not have to respend the time relooking.