My vote goes to a CZ 75D Compact PCR. It's a GREAT little pistol, and fits my needs perfectly. It's light, compact, and I really like the decocker instead of a safety (I don't care for safeties, and I REALLY don't like lowering a hammer on a live round w/out a decocker.) I picked mine up for $400, at a local gun shop.
If I couldn't find this pistol, and had to choose something else, I'd probably look into the HS2000/Sprfld XD. Well, I guess the Springfield is actually priced out of your range, so it would be the HS if you could find one. I liked the sample I fired, and it was quite accurate.
I had a Firestar in .40 S&W which I carried for a couple years. It's a great shooter, with fantastic accuracy. It would do some quirky things sometimes (drop the slide and the hammer fails to stay back, fail to go into full battery, etc.) so I finally had to switch carry-guns. I sold it a few years ago for $275, $25 more than I paid for it in 1995. I would give it a decent rating, but you could do better w/ your budget.
I have no experience w/ a Kel-Tec P11, but my P32 has been full of headaches. YMMV. Unless size and weight are your two most important factors, why risk it with so many other great guns out there?
I like Taurus revolvers, but I have heard horrible things about their autos (mostly about the Millenium series.) I can't recommend or give evidence regarding any of these. If a revolver was an option, I paid $400 for my 617t (7-shot .357mag, total Titanium, snubbie.)
The Kahr would also be a great choice if you wanted a REALLY small pistol. Good quality, just a little too small for my big hands (my thumb kept engaging the slide-stop while firing.) This particular pistol has proven VERY well for many people. Don't pass it up without checking it out.
In all- I went w/ the CZ PCR. It fit MY needs perfectly. You'll have to get out to the local ranges and try these different pistols out for yourself before you can make the best decision for YOUR needs. Enjoy the shopping experience, you can learn so much about what's out there and maybe a little about yourself.