Quote Originally Posted by AMay View Post
I will probably wind up making my own optocoupler with the smallest 120v bulb I can find unless I can find a better ready made solution.
There are AC optocouplers intended for sensing presence of mains voltage.

However, since this is a PIC forum, Microchip AN236, which is about controlling X-10 devices, shows how to detect mains zero-crossing just using a 5M resistor and the built-in clamping diodes (on most PIC pins).