The way they work has been described in TrekLit.
*prepares for technobabble*
They have them listed at Memory Alpha.
*prepares for technobabble*
It is based on generating a destructive subspace compression pulse. Upon detonation the torpedo delivers the pulse in an asymmetric superposition of multiple phase states. Shields can only block one subcomponent of the pulse. The other subcomponents deliver the majority of the pulse to the target. Every torpedo has a different transphasic configuration, generated randomly by a dissonant feedback effect to prevent the Borg from predicting the configuration of the phase states.
They have them listed at Memory Alpha.