One thing akbound didn't mention, and it might not be a concern in your state: some states don't allow concealed carriage (or any "on person" carriage for that matter) within a vehicle, i.e. here in Kansas you can openly carry whatever you wish as long as municipal legislation or business policy doesn't prohibit it, but as soon as you get in your car, you've got to take it off, it can be openly displayed in your passenger seat, locked in your glovebox, displayed on the dash, etc., it either has to be off your person and in sight or locked and out of reach of the driver, i.e. under seat compartments, storage compartments between bucket seats and in-door compartments in the drivers side are illegal, locked or not.

Ankle holsters are great if you can legally carry in your car, I can't wear them because I wear high stoved cowboy boots, I prefer a holster in the small of my back or behind my belt buckle when I'm carrying concealed.

One thing on your carry gun...you might consider a .38spcl or .45colt (or .45superbond) two barreled derringer. I bought my Cobra Inc. (formerly Davis enterprises) .38spcl O/U derringer for $70, for any personal defense scenario, it's great, small, flat, slim profile, and plenty of power on the out end, only two shots but I'm a crackshot with it, and stats show that less than .1% of cases where a gun is drawn in self defense ever require more than one shot, less than 10% require a shot at all. I've also got a Ruger P-97 .45acp that I keep in the glove box, in case I need more shots while in my truck.