If you want to find out more about Dianetics and Scientology, the best way to do this is to read an L. Ron Hubbard book on the subject. I personally recommend you read The Scientology Handbook.
This book really helped me with understanding what Scientology and Dianetics are all about. It gave me an overview of many of the areas that concern Scientology and gave answers to what is being done in each area.