Hello I am wondering if somebody has figured out a good technique to mount the camera to shoot a God angle or "God shot", straight down from the ceiling. I am using a Canon 7D with external monitor. I would prefer a wide angle lens to shoot for example a normal living room on location.

Simple, rent a jib & a strong tripod to mount it on.

Or if you don't have money for a jib, you could use a tall step ladder. The step ladder will probably take up less room too. It's certainly no more conspicuous. How big is the "normal living room", and how many people will be in the shot?

There are also camera mounts you can purchase that mount to studs in the walls and ceilings. We have several of those at my church for the remote controlled cameras. I think they have the standard 1/4" twenty thread screw mounts. Our remote cameras are about the same size and weight as your 7D.

But again, if it's a one time deal, why not just climb up on a stepladder and shoot? I've climbed them, and staircases, and up onto roofs, and even climbed up into trees to get shots. Of course, that gets harder the older I get.

Yes,
We have all done the stepladder shot. Just keep in mind that it is easy to get carried away.
If at all possible have a grip holding the ladder steady and perhaps C-clamp the tripod head on a riser to the ladder.
A jib is the best option but if you don't need to "dolly/swing" the shot the ladder thing will work.
Be careful and get that shot!