I need to pull electrical before the walls go up!

I want to put a wall sconce in the landing going down to my basement. Thee was a light there and it had it's own switch for off and on but my new wall sconce does not. What would be my best way of adding it: 1) There is a switch already at the top of the stairs that operates the light at the bottom of the stairs. Can I just wire the light into that switch? 2) The old light has it's own junction box wired live. Should I add a second switch to operate the sconce? What I would really like to do is operate the sconce and the light at the bottom of the stairs from the same switch and put a 3-way switchs in so it can be turned off at the bottom of the stairs too. The junction box for the sconce light has a black and white wire in it. The wall switch at the top of the stairs has two white wires two black wires, one red wire and a black pig tail wire going to the switch. The white wires are tied together with a marette, the two black wires are tied together with a marette and the black pigtail wire is coming out from the two black wires to the switch. The red wire is also going to the switch.

I recently bought a new house. I think its about 60 years old or so. I need to convert a switch to an outlet? My neighbor says I can take the wires from the switch and put them on the hot of the outlet and run a wire from neutral to the screw on the box. It works well but i just wondering if this is safe. Another issue is with another outlet. is it possible to have a receptacle with a seperate circuit on the top and bottom outlet. In the kitchen there is one receptace but there are two circuits coming in through the wall (one is not used). I want to hook up a fridge and a microwave and I know the one circuit cant handle it and I dont want to tear up the wall to put in a bigger box if I dont have to. Any help would be appreciated