Yup, I'm voting tomorrow. I am guessing when will be a quiet time will rather depend on your area, but I would guess that mid-morning or mid-afternoon would be the quietest. Before work, in the lunch hour and immediately after work will probably be busiest as anyone working will have to fit voting around that. We'll be heading over about 11 I think, but last time I went to vote I was literally the only person there! Although I am guessing this election things might be a bit busier.