The greatest way I have found of meeting new people is to go along to the Newcomers Group at Discovery Bay Residents Club (free to anyone). Check with the club which day it is. There is a lovely lady who has been in DB for years who hosts the meeting and will answer any questions you have.
Otherwise, I go along to the Discovery Bay American Womens Association Meetings which are held on the 3rd Thursday of every month. Again, you do not need to be a member to go along. It is hosted in someone's house and it a very friendly atmosphere and during the meeting the host, Lorraine, will talk about all the different social groups happening in DB that you may wish to join in with - hiking, majong, scrabble, book clubs etc etc. Please email me at [email protected] if you want more details.