You might want to look into coast to coast or passport america. I belong to travel resorts america (they only have 2 campgrounds but I got a coast to coast membership with it). Another one to check out would be camp club I have heard people talk about passport america and camp club but don't know a lot about them. Sorry this isn't more helpful.
2014 Chevy Silverado 3500 SRW Duramax
2011 Zinger ZT26BL
Reese Dual Cam Hitch
***Member of the Mason-Dixon Group***