So how do I go about adding new third party content, like say Victoria to Poser?  I know this is a real newbie question, but I searched the 3 manuals and quick start and can find no references

Thank you

First, do you own Vicky (version3 or 4)?  Both can be downloaded from DAZ3D.  The files are packaged in their installers.  Click on the execution files and follow the installation wizard. 
Second, the Poser manual does not cover 3rd party installation; it is not part of the Smith-Micro's product offerings.  However, ContentParadise, in association with SM, does sell other 3rd party character content which are packaged in zip format.  RuntimeDNA also some unique characters. 

 I have  the victoria4 exe file and I ran it , it is pointed to poser, so what files do I extract to where?

After pointing the installer to your Poser directory the installer will automatiaclly install all of its files where they need to go.  Then when it is done it will allow you to launch a Readme page that will tell you where it instlled the content

 OK I did that found the read me, so how to I get this model to show up in the libraries figure tab in the pose window for poser 8?

After installation, there should be a v4.2 update icon on your desktop.  Make certain you run the update!  Afterwards, navigate to the figure category in you library and you should find V4 under DAZ People.

 Thanks, I got it!

Don't forget M4, M3 (Mike, base is free), Hiro and Aiko 3 (also free), in fact, I don't have the actual URL, but there's a (legitmate) sige where All the millenium figures ( the ones that have abbreviations like English motorways...;) are all in one package.

Check freebies here; there's a few more available, search on categories as Poser, and load up on freebie characters from there.

That site is www.downloads.com.  Link below:

http://download.cnet.com/Poser-DAZStudio-3D-Models-Pack/3000-6677_4-10579249.html?tag=mncol