Maybe. I'm with rcmodel completely. Picking the 'most effective' man-stopping pistol is flawed on its face. Most people who are hit with a single bullet from a pistol will run away. I will ALWAYS advise people to carry the most powerful pistol they can shoot well, because it's a losing game to begin with, and you need all the advantages you can get when you are fighting for your life.
I USED to say that a .380 is the bare minimum to carry, particularly for people who absolutely must have a deep-carry piece. (NOT for regular guys who are just too lazy to adjust their wardrobe and lifestyle to carrying the weapon they shoot the best.) But then in about 1995 I think, I was blown away by the sub-compact Glock. Suddenly, it was possible to carry a tiny gun in 9mm, .40, .45, or .357 SIG. WOW. concealability AND power. These were followed by a lot of other sub-compacts in bigger cartridges. Now there are Kel-tecs, Ruger, Rohrbaugh, etc. in 9mm that are quite reliable. I've never heard anyone give a convincing reason to carry a .380 INSTEAD OF one of these options.
However, I might steer you toward a Makarov. Cheap, brutally reliable, and I am not afraid to shoot Wolf through it. (I have a rule, Russian ammo ONLY in Russian guns.) This reduces the cost. A good friend of mine has one, and keeps it as his 'floater'. The one he can loan to a friend, put in the glovebox, put in an ankle holster, beat up, etc, and he won't get heartbroken if anything happens to it. I would go to a gun show and get a feel for the market.
But honestly, I am not aware of a problem that the .380 could solve, that can't be better solved with something a little bigger and a lot more powerful.