All homicide rate data is from the online database for the Centers for Disease Control. All other data is pretty much from the Violence Policy Center web site, except the "around 8%" of women owning a firearm. Their site says 6.6%; some other stat I found (sorry, didn't track it too closely, you'll just have to do a Google search) said 9% -- I simply averaged the two and rounded to 8%.
The one remaining thing is my estimate of percentages of white and black women who own guns (about 8.5% & 5%). I derived this algebraicly from the following assumptions and round figures: I assumed 69% more white women own guns than black women, since that was true for all whites (both men and women). That's an assumption, but was the best info i had. Then I said, let's say 85% of women are white and 15% are black (I left out hispanics but since their homicide rate is similar to that of white women, I don't think it should matter). Then I calculated, on the basis that 8% of all women in America = the # of white women with guns + the # of black women with guns. The # of each is = % of each times the # of white/black women in America.