Link for the adapter please?
this: STANDARD AUDIO ADAPTOR FOR 8100/8800/8830 - ADA-BB8100M35FST
or this: AUDIO ADAPTOR WITH BUILT-IN MICROPHONE AND ANSWER BUTTON (2.5MM MALE JACK TO 3.5MM FEMALE JACK) FOR BLACKBERRY 8100/8800/8830 - ADA3-BB8100M35FST

Also, a (different) vzw store near me was out of the adapter Jackyerlate mentioned, so I may end up ordering it via my b2b site.
I've ordered the stereo headset direct from RIM:
BlackBerry Accessories Store - Product Detail

much thanks for everyone's help!