ATLANTA (AP) Once or twice a week, the women's drum circle gathers to practice. Drum Sista's members pound and caress the skins, bonding through the rhythm in an atmosphere of like-minded women activists and artists, all African-American, all lesbian. It is no accident that they found one another in Atlanta. The city and its suburbs have, in recent years, become a mecca for black gays and lesbians. The region now is home to the biggest concentration of black same-sex couples in the South, with nearly as many as the Chicago area, which has more than four times as many blacks....