It probably varies across the nation but here in the Cleveland, Ohio area they were still doing Knob & Tube wiring in the early 60'.
I'm going to guess that it took city areas longer to change over then smaller comunities. The reason I say this is that here in Cleveland the electrician unions were against the change over because it took more workers on a job to install K & T then it did Romex.
If you have romex coming into the switch box and there is only one romex cable, then there is no usable neutral. There are a few ways to wire a light, switching the hot side, switching the neutral side, bring in power at the light first or bring in power at the switch first. Your best bet if your not sure is to have an electrician look at it and make recommendation on how to get you what you need. You don't want to get hurt or cause a fire by guessing wrong.
Understand that there are right ways and wrong ways to do things and even some electricians take short cuts though most take pride in their trade and do it right.
(http://www.bdshost.com/X10/lpup.gif)---(http://www.bdshost.com/X10/lpup.gif)---(http://www.bdshost.com/X10/lpup.gif)---(http://www.bdshost.com/X10/lpup.gif)---(http://www.bdshost.com/X10/lpup.gif)----KDR
When I remodeled the kitchen and did the wiring I had to remove any K & T wiring going to any fixtures in the kitchen and install new romex to current standards. When I installed a new main circuit panel I had to install city minimum which was a 125 amp main. Since the wiring coming from the pole also had to be changed a new meter box and weather head had to be installed. New conduit had to be installed to meet size requirements for the 3 main cables. The meter box as well has the main panel had to be bonded. I was allowed to bring all six K & T circuits into two 4 x 4 junction boxes, 3 circuits per box, and then tie them into romex cables that then went to the new main. Since the old K & T circuits were 14 Ga. each was fused on 15 amp breakers. This may not be allowed in all locations and special permission to do it this way had to be run past the local inspector prior to doing it.
Needed the permit thing so local electric company could change the wiring from the pole... else I would have skiped that step :'
(http://www.bdshost.com/X10/lpup.gif)---(http://www.bdshost.com/X10/lpup.gif)---(http://www.bdshost.com/X10/lpup.gif)---(http://www.bdshost.com/X10/lpup.gif)---(http://www.bdshost.com/X10/lpup.gif)----KDR