To download the header files, libraries, and documentation for EAX 2.0, go to:
http://eax.creative.com/developers/
The I3DL2 standard was created by the Interactive Audio Special Interest Group (IA-SIG). For more information go to:
http://www.iasig.org/wg/closed/3dwg/3dl2v1a.pdf
To utilize the SDK for 3-D audio by Sensaura, which offers some property set-based features in addition to EAX 2.0, go to:
http://www.sensauradeveloper.com/
Creative Labs and Sensaura are not the only companies to provide property-set access to their hardware. NVidea, C-Media, Yamaha, Philips, Crystal Semiconductors, and no doubt others have also enabled property sets covering EAX, I3DL2 or other voice-management functions for their sound cards.