What's with the misconception that techno is usually not copyrigthed? While it's easy to find freely downloadable techno music it's still mostly copyrighted (everything is automatically copyright protected unless the authour says it isn't). That means you can't do whatever you want with it, even if the author lets you download it. Things such as reproducing, selling, playing at clubs and redistribution are restricted.
You should contact the authors of the music you use and ask if it's okay, and give them the credit they deserve.
