In many cases, the base textures use shader nodes for specific enhancements.  Perhaps you should confine your search to texture maps in Poser or shader nodes in Poser.  You should get some potential links that would be relevant to what you want to accomplish.  If you need an understanding of shader nodes and what they do, the link below will cover each node in illustrated detail.

http://www.castleposer.co.uk/articles/nodes_vocab.html

Do pick apart the textures of objects in the material room; that is the only way that you can determine how nodes are arranged and why.  Most times I go into the Material Room to change node values, correct potential obvious mistakes, clear out extra nodes (Oh yes, authors do forget to clean house sometimes) and add extra nodes I may generate in other software.