What do you recommend for a lady that is affordable, user friendly, and effective as a self defense weapon? (I will also be seeking a concealed carry license so it needs to be portable too.)
One place to get a look at pretty much every sort of thing you'd consider in one place would be gunbroker.com which is a sort of an ebay for firearms.
You have several choices, the most major being between revolvers and semiauto pistols. Many people, particularly cops, figure you're always better off with the revolvers, which they deem mechanically simpler and foolproof.
You'd want some sort of a small 38 caliber revolver if you go that way.
The most major advantage of the semiautos is the ability to reload quickly (by changing a magazine) in some sort of a sustained gunfight with pistols; in real life, the chances of YOU ever being involved in a sustained gunfight are probably exactly zero but there might be other advantages to semiautos which would be meaningful in your case
Revolvers arose in the age of black powder which was much less efficient than the smokeless powder used today and for that reason many of the cartridge calibers used for revolvers (which are loaded with smokeless powder today) are overkill for human adversaries and better suited for protection against bears and other dangerous members of the natural order. In particular were you ever to fire one of the magnum revolvers indoors, you might never really hear again.
The semiautos arose AFTER the invention of smokeless powder and absolutely require it since cartridge cases beyond a certain length would prevent them from functioning.
The main choice amongst semiautos is between heavier calibers which require the barrel locking system which John Browning invented, and which limits accuracy, and smaller calibers which can use simple blowback mechanisms.
For a small, light semiauto pistol which would still stop 99.9% of all evildoers from whatever evil they had in mind I'd recommend some sort of little 380-caliber semiauto, and I'd make sure to experiment with different kinds of ammo for it until I had one heavy enough to guarantee that it never jammed, i.e. with which you could fire off a hundred shots without it ever jamming.
Something like this would do:
380 Would be the largest semiauto caliber for which you could get by with just the blowback mechanism, which would make it my choice for what you're talking about.