To paraphrase Access All Areas:
If you can't find a site... open your eyes.
The same thing applies to finding people in your area. It seems to me that finding people and locations is something that's harder when you first start exploring than when you've done it for a while. To cite an example:
I met a user called RichterScale on Saturday. He PMed me after I posted something about a location in Cincinnati and we decided to go check out a location together. When we were there he told me that he and his roommate went exploring sometimes together. I also saw a graffiti tag someone did of their instagram name. We also saw another group of explorers there (maybe 3).
So far I found two additional people to go exploring with.
I DMed the instagram user and asked if they wanted to go exploring sometime. They said they were totally down and it turns out that instagram user is actually a group of three guys.
The point I want to make here is that I met 8 people I could go explore with in a few days' time. It is always harder when you first get into it. That being said, here are some ways you could try to meet some people: Check UER
If you click on the "Members" tab in the sidebar you can do a location search and see if there's anyone not too far from you.Ask anyone else you know
If you know any fellow explorers ask them to introduce you to new members.Ask Google
Do a search for locations near you and if you can find any websites, try to contact whoever made the site and ask them to check a site out with you, or at least introduce you to some of his friends.CraigslistSocial NetworksGraffiti
I have seen people graffiti there contact info on walls. I don't approve of vandalism but if you see tags with exploration or urbex in the name I'd check them out. Random phone numbers I would avoid for obvious reasons.
The list goes on. There are a million ways to find people and the only reason you can't find people is because you aren't looking hard enough.
edit: Fixed my little typos