How to take really amazing photos like this (links included)?

So i have a tumblr account and i always see these amazing pictures that in my mind scream "cool alternative looking with awesome lighting" like this:

or this:

and i would love to be able to take photos like that with that lighting. Is it an effect added to a photo later or is it the camera that captured it? People have facebook profile pictures like that too and it is just amazing and yea, so thank you so much!
ps if it matters i would be doing the editing on a mac book pro and i have a nikon d7000 (i think, its either that or the 6000 i don't remember)

I'm one who loves photography. And all you need to do is to get a friend or a parent.mabye if its snowing near you, you could go into the snow with your back towards the camera and try and capture that? That'd be a really neat picture! Hope that helps=)

The first one may be as easy as changing the exposure setting on you camera if you have one you can set first to manual. The other option is Photoshop. The second can also be done in Photoshop but I just bought a Nikon D3100 that allows me to make any picture a sepia tone picture right in the camera. Try Photoshop Elements (9 -I think is the most current).

Go look up photoshop actions on the net. And it will give you a set to create different looks. That is how they are getting the effect it is not a camera setting.

They are not that amazing they were just shot into the light.