Check out the Vancouver Bicycle Meetup Group. They have several ride leaders based in New Westminster. Also, there is a Vancouver Bicycle Club. I don't know about the roadie scene, but I think Mighty Riders and La Bicicletta (both in Vancouver, on Broadway) can put you in contact with serious roadies.
2 bike shops come to mind in New Westminster: Cap's and New West Cycle. Oh, Burnaby has Jubilee Cycle (on Imperial, close to Metrotown): the owners have a competitive road racing legacy so they likely know of clubs.