Contaxis/Najera/Estavane of Greece/Mexico/Spain

I am currently researching my late mothers side of the family, she died last year very suddenly. My grandparents met and married in ElPaso, then moved to California. Her name was Teresa Najera from Durango Mexico, his was Demetrios Emanuel Contaxis from Greece (Samos). I know Nothing about my great gradparents and each place I turn I hit a brick wall at finding any roots from the other countries. Any advice or help would be greatly appreciated. Thanks Bella