With PackfileExplorer version 3.9, you may view and extract the models but not as source .smd files.
PackfileExplorer will not work with every model.
You can download the latest version here:
http://paine.planetvampire.gamespy.com/vtmb/files/download/590/Alternatively, you can decompile the models with Gardeb's decompiler and recompile with valve's source engine studiomdl compiler and then view the model in hlmv.
Gardeb's decompiler can be downloaded in this forum but it does not work with every model.
Creating tools that work is very difficult as Troika heavily modified the source engine that they licensed.
None of their modifications exists as features in the current source engine.
They used a quaternion based skinning algorithm. They implemented a hair, cloth and soft body physics simulation system. They use a flexible quaternion third person and first person camera system. Their facial animation system is mpg based and uses lip files. They rewrote the bsp scene graph for a night based lighting model. I can go on and on. The number and breadth of changes made to the source engine is so substantial that reverse engineering their improvements to the source engine is a daunting task.
With a little hard work, it is possible extract something that you can work with.
Here is an example:
SmilingJack.rar
http://rcpt.yousendit.com/641086148/0cb2782e79b1f25208a4c7c273497a4eOnce downloaded, recompile with the source engine's studiomdl compiler.