Wicca is a hard belief system to study as both Wiccan and Paganism stand by the belief that most of the historical docutments and history was lost during the 17th and 18 century.
Wicca was based on christianity beliefs and earth worship. Your best bet to gather info is to join online Wicca communities and ask around for members that have been in practice for a while. There are also a great deal of books written about Wicca and its belief system. In my experience everyone is willing to help educate others about thier faith and lifestyle.
