How have you been searching? I would trying call the Property Managment companies for the homes that have the HOAs and ask them your question. They may know.
http://schertz.com/documents/HomeownersAssociationRevised-1-
Have you talked to any local agents? Most will talk to you without any obligation. I do that all the time. I don't even ask for a name unless they want to offer it. I know people value confidentiality.
Yahoo has a decent search engine:
http://realestate.yahoo.com/Texas/Schertz/Homes_for_sale/res
You may want to consider a land purchase and build your own.
Tried Trulia as well?
http://www.trulia.com/TX/Selma/
Good luck and happy hunting!
- A few minutes ago