I'll second what everyone else has said... a 9mm or .40 won't do much for bear defense. A .45 is probably a little better, but I wouldn't want to face down a bear with anything less than a 12gauge with #00 buck. You can get an 18" - 20" Remington 870 for ~ $300, and there's probably no better value for home defense.

I would also recommend playing around with any handgun you consider purchasing at a gunshop. Further, I would recommend renting some different models at a range and shooting them before making a purchase if possible. I shoot my Glock 22 and 27 (.40 cal) very well, but I've shot 3 different 1911s and am a very poor shot with them, and don't like the way they feel in my hand. The shape of your hand and the way you grip the gun plays a lot into how comfortable/natural a gun is to shoot, and in a self-defense situation you want a firearm that is easy to shoot "naturally" rather than something you have to remember how to adjust your grip in order to hit your target.

So I'd say a 12 gauge for home defense and a 9mm for carrying, as it will be the cheapest to shoot and the easiest to practice with while still having enough oomph to take down non-bears.