I've been networking to meet investors for the healthcare properties I'm working on as well as private lenders.
Generally, and not to be cliche, it's all networking; however, typically in unlikely places. The BP meet up I go to in my area was a great place to start. I also met many people looking to invest through some of my hobbies (boating clubs, motor enthusiast clubs, etc) - so golf / country clubs are probably good too (though I don't belong to any either of those).
Former co-workers and my professional friends have also been potentials, particularly for referrals.
Speaking of referrals, I think once I hit the later stage of some of my deals, my few current investors may open me up to their friends and networks.
I haven't tried this yet but I've heard LinkedIn is a good place to network if you can establish your credibility in what you're doing.
Finally, you can look for "trust" or "IRA" on the county records for either the owners or mortgages.
Hopefully, those are helpful.
Thanks,
Suhan