3spur, since you're thinking of a semiauto you're on the right track with the Glock 19 or Ruger SR9. 9mm is a flexible and economical round, you can do most practicing with cheap ammo then buy good self defense ammo for normal carry. Of course get confident with the SD ammo at the range too. 40S&W and 45ACP are great calibers but many women might like the lower recoil of a 9mm. Of course good defensive ammo is going to have a kick, even 9mm.
There are two versions of the Glock 19 for sale now, the older Gen 3 and newer Gen 4 (which is hard to find in California I've heard). The Gen 4 has adjustable grip sizes which can be an advantage. The Gen 3 is a pretty good compromise for most people. Whatever you get make sure it fits well and you're comfortable with the controls. Some semiautos, especially SA/DA are pretty complex to operate at first.
I'd try to handle, rent and fire as many handguns as possible to find the best one for you. Not a bad idea to try to include a Hi Power and 1911 just to see how they feel in your hand and their extra heft over the Glock, Ruger, M&P, XD polymers. They are heavy but have less recoil.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
US Army 1966-69, VFW Life Member, Retired Geek