I have a few suggestions - none original, but perhaps they will trigger other suggestions from the board.

1. Look for a death record for John (TX: 1903-1940)

2. If you don't find one for John, try looking for another close family member (did his wife die later?). Perhaps they were buried in the same place.

3. Check to see if the local Historical or Genealogical society (Waller County) published a list of Waller County cemeteries.

4. Do you know his religious affliation? You can search for existing churches (hoping to find an OLDER church that has a cemetery of choice OR a contact that would know the area).

5. Rootsweb site for Waller County - history / cemetery list.

6. Waller County Historical Markers -- AA churches? cemeteries?

7. Check the local Public and Private Libraries/Archves (county, City, University) for histories of the area's African-American population. Perhaps there will be a list of organizations (churches) that existed at the turn of the century.
** Note **: Prairie View A & M is in Waller County.

8. Search for existing Waller County funeral home records (resources) - around that time frame.

9. USGS (Geographic Names) can be searched for 'church' or 'cemetery' by county/state.

10. Old newspaper/directory search - history, mention of churches/cemeteries.

11. Search for additional resources on CyndisList (Texas)