We stayed at the CBR in May and I did notice that they had a vollyball net on the beach. I never saw anybody playing (we were mostly at the parks) but I would assume that they provide the ball.
I've never seen beach volleyball at the GF, but I do know that the BC has a sand court. The ball is kept at the Ship Shape Health club. It's complimentary to YC/BC resort guests, I don't know about anyone else though.