I don't believe the 201 has a button for the light. It should come on when you plug the machine in.
Sew-Classic has a lot of parts for your 201 machine including the wiring for the machine and the foot control.
http://shop.sew-classic.com/Singer-2...-Parts_c36.htm
I've never bought from them but this site carries the bobbins and the bobbin case for your Viking machine
http://www.thesewingoutlet.com/husqvarna-viking-6690/
This one is a little cheaper
http://www.sewingpartsonline.com/vik...ine-parts.aspx
Here is the owners manual for the Viking
http://www.scribd.com/doc/46993586/V...wners-Handbook
Here is a manual for the 201
http://www.scribd.com/doc/206162301/...Machine-Manual