Actress Vivica A. Fox ("Kill Bill," "Curb Your Enthusiasm") is in town this week working on her Vivica A. Fox Hair Collection, based in Conshohocken. Today and tomorrow, she's doing photo shoots for promotional materials, and on Saturday morning she'll appear from 10:30 to noon at the Cambridge Discount Plaza (1500 Mount Ephraim) in Camden and from 2 to 3:30 p.m. during a hair show at Hair Town at the Cedarbrook Mall in Wyncote.