The members' area lives on the main Society site and uses the login the secretary sent you when you joined. Log in there and these open:
The Town Centre Survey
The survey of the historic buildings and features of Wigan town centre.
The Douglas River Project
Sites and finds recorded along the Douglas valley.
The Artefacts and Monuments Record Database
The Society's record of artefacts and monuments in the district, with locations and photographs.
Wigapedia
The Society wiki: articles on the archaeology and history of the Wigan area, written by members.