Upload & Sell: Off
Let's take this one as an example:
Amy Rose by Ian_Boys, on Flickr
It is shot at iso 1600 using the in camera b/w JPG setting with no JPG filters. None of them do better for skin than the standard b/w, whatever they say. I set the camera to 1:1 for composition and don't go too close. I am using a large video light (about 2 foot across) and a lot of the look comes from the fact that it isn't a point light source.
Re focus - I wouldn't bother manual focusing a shot like this. Move the AF point around and put it on her eye. Easy and very accurate.
Lastly - don't use f2. Take a photo of some newsprint at f2 and f2.8 and f4 and see the massive difference!
For post processing I use Silver Efex 2. Sometimes nothing, if the original file is very good and often it is.