Thanks to your responder - I never thought about Facebook. Back when I actively hs'd it was Yahoo "groups"...
but a cursory search turned up:
https://www.facebook.com/groups/scsecularhomeschoolers/
https://www.facebook.com/groups/565560290146344/ (Sometimes the SAY they're inclusive, but really aren't, but worth a look)
https://www.facebook.com/groups/homeschoolingcharlestonstyle/ (These may be the unschoolers of which you speak - though it may not even be Chas, SC. - I used to know the - nothing but "unschooling" type, though we got along well enough. We were an eclectic whatever-the-hell-works "car" schoolers. lol)
There are probably more.
However, one thing I did - living in WAKE FOREST, NC - home of the originator of the fundamentalist movement that destroyed - er - changed the Southern Baptist Church - I put up flyers in the Library and other gathering places saying what type of hs'ers I was looking for. One phone call led to a small group of us that met for about five years before we moved. They continued for another two or so until the kids were all teens. Those kids are still friends even though they're spread around the country.
Oh, one more thing - some of our members were "religious" but they weren't hsing BECAUSE they were religious. They weren't dogmatic, they didn't use religious material, and they were very liberal. We had two Methodists, an Episcopalian, a couple of pagans, an agnostic/atheist, and my son was Buddhist for a while, and an American Indian "spiritualist'. Good group. Sometimes families would visit our group, and decide we were too liberal and move one.
I found words like "secular", "liberal", "tolerant", and inclusive were good words to weed out/in people.
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