Update 1: ThinkProgress has an excellent post on the decision that you can go to for more info. Justice Ginsburg wrote a scathing dissent. Here's an excerpt:
...the Court’s opinion tolerates, indeed applauds, federal intervention to ban nationwide a procedure found necessary and proper in certain cases by the American College of Obstetricians and Gynecologists. For the first time since Roe, the Court blesses a prohibition with no exception protecting a woman’s health.
Update 2: Both NARAL Pro-Choice America and Planned Parenthood have actions up on their websites to take. These are organizations on the front lines protecting a woman's right to choose.