Hi, I can't believe nobody has responded to this yet. 

Just need to clarify things a little. The new hair feature in Carrara 6 is not exportable to anything else. However, if you want to make geometry based hair (which most of the for-sale Poser hair is) then you can use Carrara for that. 

There are tons of short little tutorials out there specificaly about making clothes for Poser characters. While there are only a few that I'm aware of specifically for Carrara, they all are really interchangeable. Just do a search in the tutorial section here at Renderosity or google a search. It's not difficult but is a multi-step process and you do need to know how to use the vertex modeler.

Finally, if you want pose-able clothing that you can sell for Poser/DAZ Studio/Carrara, you'll need to do the rigging in Poser itself. You can rig clothes in Carrara  for use in Carrara but the Carrara bones don't export out to Poser or Studio. 

Mark