I'll second Al Warner as being the first in-home arcade invite I got. A couple of years back I remember getting really obsessed with pinball. I can't pinpoint exactly why, but I did. My wife and I drove down to Panama City, FL for a yoga workshop she was doing and I spent my time trying to find a pin on location. I was disappointed to find only 1 - NASCAR. Not being a fan of NASCAR at all, I was disappointed, until I started playing. For less than $3 I played for an easy 90 minutes and had a blast. I didn't know what the knocker sound was for, but heard it a few times and the people at all the cash suckers around me kept giving me and the game strange looks.
Fast forward a couple weeks and I had done some online searching and found quite a collection of collectors/pinheads in the Atlanta area, about an hour and a half away. I hit up Al about an open house he was having and never having met me he said we should come on up. His collection was really impressive, pins, vids, and a super awesome 6 player EM bowler. That was it for me. After that I was hooked.
Really the entire Atlanta community is great, tons of really great collectors, players, and many of the first friends I'd made in ages, mostly because I found something to really share with others.