At a broad level, he uses Ableton Live, which is popular with many similar producers such as Deadmau5. He also uses a Pioneer DJM 800 mixer and an EFX 1000 for effects.
Sonny works with two computers. One running Ableton Live the other one Traktor Scratch Pro in combination with NI's Audio 6. He uses timecode cds in his Pioneer DVJ-1000 and the Audio 6 connects the Pioneer DJM-900 and therefore the timecode signal coming from the DVJ-1000 to Traktor. Furthermore he uses an M-Audio Trigger Finger to control Ableton on the other computer.