Ah, I’ve seen work like this before. It’s not something you generally do with Photoshop, unfortunately. It’s all in the photography itself. The photographer most likely uses several cameras (or takes several photos) that can individually focus on different parts of the composition, so both the people and the background can be completely crisp and in focus. They also use different lighting techniques to get all the contrast and luminosity you see. These’s Photoshop work involved too, I’m sure, but you can’t just take a normal photo and make it look like the examples you gave. Dave Hill is a good example of a photographer who does this kind of stuff. If you click on the “Behind the Scenes” link on the bottom of the page, you might be able to get some ideas of how he does this.