OKay different people are going to tell you different things, especially about the whole feeding in or out of their enclosure issue. When deciding upon feeding in or out, you have to kind of experiment a little, see how well your snake does in or out, and also it can be based upon your own preference too. I myself feed my girl live and in her enclosure. She won't eat f/t for me and has eaten much better for me in her enclosure. I think that she just feels safer in her enclosure, which makes her more relaxed and ready to eat. I get my feeders from local petstores, although I guess maybe I am a little lucky and have found a number of smaller family owned type petstores near me that have much better quality feeders. In that issue you just kind of shop around a little, ask to see the feeders before you buy them since a lot of times stores will keep their feeders in a back room. There is one store near me that keeps their feeder mice in a tank where anyone can see them on the salesfloor. When choosing feeders just make sure that they don't look all sickly. They should have nice coats, nothing running out of their noses or near their eyes, and have quite a bit of energy. I also get my feeders a few days beforehand, I have a tank set up for feeders so I can continue to watch them to make sure that they are healthy (I have had feeders before look good in the store and then just die overnight....I don't buy my feeders from that store anymore..) and also I make sure that they are well fed.
When it comes time for actually feeding my girl, I usually will hold the mouse with some tongs until my girl starts poking her head out of one of her hides. I can tell when my girl is ready to eat, she gets her striking pose all ready (S shaped neck, tongue flickering alot, extremely focused) and that's when I release the mouse in the tank. I don't stun my mice, my girl can take care of them very well on her own. Usually she's got the mouse in a couple of mins. and then it will be completely gone shortly after that. Make sure you are always watching though while feeding live. There's always a possibility that 1. she won't take it (with my girl she hasn't ever refused live, but I would take the mouse out if she hasn't gotten it in about 20 min) 2.the mouse could try to hurt the snake then you would have to step in and prevent your BP from getting hurt