Most of these songs do not have much material below 30hz and some not even getting that low... wow.
That song only dips down to 34hz... sorry but that's not even close to what the OP wants nor is it low at all.
It's hard to get suggestions for music content that low when most systems don't do well below 35hz anyways.
I have a decent to small collection of music with content below 30hz and I have uploaded three tracks. I will upload more later today but let me know if you like these songs:
http://files.filefront.com/Lowzip/;11542881;/fileinfo.html
The 3 6 song goes down to about 22hz, the Bassotronics song's bass line is centered around 30hz and 19hz, and the last song is Pump Up slowed down and has breakdowns around 28hz and 25hz with some even lower 20s action.
I love listening to music get down low so let me know if you find anything worth while.