Sandstorm is not techno (its trance.) If you want a real techno song it depends on what techno we are talking about. If you want the original style of Techno, which is Detroit Techno. You need to get Good Life by Inner City. If you want more darker minimalistic Techno, Energy Flash by Joey Beltram would be sufficient.

Of course be aware that what you were hearing may not have been techno. There are many different forms of electronic music.