We've also offered both equity and non-equity "access" to our LLC's aircraft to a couple of people we thought we could all get along with. One was a co-worker of one of our co-owners, the other I met via Ham Radio.
One decided to fly LSAs, the other had a family fiscal "event" come up that had to be taken care of, which will take years to pay off and has effectively grounded him. (Two words: Restaurant business.) Bummer.
I bet there's a lot of co-ownerships out there who aren't out actively looking for additional members, but if a sane and responsible person asked, they'd think about it for a while and say, "Well... sure... why not? Here's the numbers, here's the insurance details, here's the MX costs, etc... you still interested?"
The other question we'd ask... "Are you liquid enough to drop $X tomorrow, if the engine goes?" Yeah, it'd be "unfair" to the new person if that happened, but the question is valid. I've heard that if you can't afford to replace/overhaul the engine tomorrow, you're not in a position to own, yet. Keep saving.
The hard part is finding the co-ownership people. The higher the airplane price, the more private/appreciative of privacy, most of these folks are. If you're not meeting them in person, you're probably not meeting them anywhere.
Ramp access is key... I have struck up conversations on the ramp about folk's airplanes that they would probably NEVER tell someone anywhere other than at the airport. Especially if they see you parking/hangaring your own aircraft, they tend to open up more.
One guy taxied out in an absolutely gorgeous Bonanza... very late-model/new, flawless... when he taxied back 45 minutes later, we started chatting and he said he'd just taken it up because it hadn't flown in a couple of weeks, and that we'd have been more than welcome to hop in for a ride... and that he and his co-owners were looking for additional people.
Out of my league, budget-wise, but just an example of "just start talking to people"... very few at the airport will want you to go away unless they're in a hurry to be somewhere else. Even then you've started a rapport for the next time you see them and they're not in a rush.
Most owners are very proud of their airplanes and will talk about their ownership setups at length if approached. Hang around the hangars and when they're open, strike up conversations... that's going to produce more real leads than a website, I think. Takes more time though.
