Your local electrical supply house. Have you tried Google?
yes I did but maybe I quit to quick. The web site I looked at had numerous pages of different switches but they were either single or 3-way. I'll keep looking.
Perhaps you're confusing the terminology (or more likely I don't understand what you're looking for). A single switch is for controlling a device (say a light) from a single location. If you want to control that device from two locations (say from either end of a long hallway) then you need a 3-way switch.
If that's not what you're looking for, perhaps you could describe you situation in a bit more detail.
3-way and 4-way refer to the number of screws on the switch, not how many locations the light is controlled from.
A pair of 3-way switches allows a light to be controlled from two locations.
A pir of 3-way switches with a number (say X) of 4-way switches wired between them allows the light to be controlled from 2+X locations.
A simple switch (two screws) allows control from only one location.