I would recommend a Kel Tec PF-9. Or for something slightly larger a Springfield XD sub compact. The Ruger isn’t bad but for the money I would rather have a Kel Tec since it is so easy to conceal.
Kahr CW 9 or CW 40. Springfield EMP. there are thousands of options and you should buy as many as you need.
The Springfield XD Compact is a great handgun in 9 mm or .40S&W. one of my sons bought one a couple weeks ago at a gun show. They can be purchased for + - $500.

I'm sure others will chime in on the quality of this fine firearm.
Rent before you buy.
You might be surprised that what you thought you wanted is not what you walk out with.
I’ve had a Ruger P89 9mm for years. Great handgun. I say get it and let us know how it goes - I might like to get one.
It shoots anything I put in it. I'm currently carrying Hornady 230gr TAP in it.
I put a set of Crimson Trace LaserGrips on it and it's surprisingly accurate for a snubbie.
Great discussion, very timely for me too. I am purchasing a conceal soon as well! Thanks everyone for the recommendations. Is the Keltech reliable? I have read some conflicting reviews. I was thinking Glock 26 or Sig p232. Hmmm choices, choices!
Various gunstore types have told me it's their next purchase as well. Designed to be reliable, more comfortable and with a better natural point of aim than Glock, over 370 law enforcement agencies have switched to the M&P's.
The compact feels great, can be worn in a large pocket but better inside the waisteband. My 9mm has very little recoil, but I haven't tried the .40 .

More concealable for sure but I'd prefer having the accuracy of the longer barrel.
Long story short, I bought a Glock 27 through their military buy program. $389 + tax + shipping + plus FFL fee. I was out the door for $470. The Glock isn't as comfortable for my hand, but it is really easy to conceal, and again has extremely reliable function.
Think a lot about the gun you choose. Your natural tendency will be for the biggest caliber you can get. When you think of defending your family against the scum of the earth, that is a normal reaction. If that gun is too big to carry in all the ways you dress then you might find yourself without the gun when you need it.
I have a Ruger Super Redhawk .44 Mag. Obviously too big for CC, but as a hand gun....I love it. It’s a gun that turns heads, as in every time I’ve taken it to the range someone has offered to buy it off me. Anything that generates demand like that from people, I’m keeping!
My primary CC weapon is a Glock 36 with a lazermax site. I also have a Ruger LCR .38 that is nice.
Don’t know much about the SR9. There is a review of Ruger’s conceal carry LCP in this month’s American Rifleman. According to the reviewer (Wiley Clapp), “It is a bit ammunition-sensitive and you have to pick your loads carefully.”
The only "problem" I've ever had with my SR9 was in the very beginning when it was brand new - it had to be broken in. I had a few FTF's but since then it's run very smoothly. So, just run a couple hundred rounds through it and you should be GTG.
On a side note, some people don't like the trigger because it feels "gritty" but I, myself, haven't experienced this.
I would recommend a Glock 26. Easy to fire, easy to maintain, and easy to conceal.
Plus, you’ll save a load of money over the .40 version.
Load it with 9mm, 147 grain, JHP and you’ll have no problem defending yourself.
Just my opinion.
RLTW
taurus pt145 mil pro 10+1 45ACP
its tiny and fits in my pocket nicely, i carry it all day every day , the best gun is one you will ALWAYS HAVE WITH YOU
as in not too big to carry
http://www.grnc.org/gun_raffle/images/taurus_PT145.jpg
That said, you might try a good .38 special revolver like the Smith model 642 or the new Ruger LCR. Load it with any .38 special self-defense ammunition you have and it will absolutely go blam every time you pull the trigger. The recoil's a little "snappy" but you can manage it, and you can also literally choose any .38 special ammo available, including 148 gr. wadcutters. I wouldn't want you shooting at ME with them.
Catch your empties in a little cardboard box when you empty the cylinder (or in your hand for that matter) instead of chasing them all over the range, save them, and then once you've got a few hundred of them (not hard to do, really) you can reload them "dozens" of times for a generous stash of practice ammo.
Whatever you're considering, "rent before you buy" is the best advice on this thread IMO.
Dirty Harry CC’ed a 6” Smith & Wesson Mdl 29 in 44 Mag.
it all depend on what you wear and do while packing.