"I can't find where the water service comes into the house and I'm WAY
too
claustraphobic to do more than just poke my head into the crawlspace.
All I see
in the crawlspace are plastic drain pipes. I think I'll just buy the
tool at
home depot and turn the water off at the meter if I have an emergency
and while
I do plumbing repairs. The meter is less than 40 feet from the front
door. "

I wouldn't rely on that as the primary shut off. Definitely not if you
live somewhere in the north, where ice and snow occur. Imagine the
water heater springs a leak or a washing machine hose were to burst.
Maybe your not even the one home when it happens. Is someone else
going to be able to find the key, figure out where the street valve is,
dig through snow/ice, etc? I'd trace the pipe, find out if you have a
valve, and if you don't, get a quarter turn valve put in.