After playing 16 shows in six cities and earning $49.7 million, Barbra Streisand may have finished her tour, but the second phase of her musical juggernaut is just beginning. Barbra Streisand: The Concert debuts Aug. 21 on HBO. Of course, she is overseeing the two-hour special, which features footage from the star-studded finale in Anaheim, Calif. ''Barbra wants to make it the most satisfying experience for the viewer,'' says her spokesman. According to a source close to the production, that includes changing the tint of her lipstick in print ads. The diva also plans to release a CD in September and a tour documentary directed by guess who. As the spokesman says: ''This tour will continue to have many, many, many lives.''