3dkaya: Sounds like you already have Zbrush, with Zbrush and Poser you're well on your way to lots of fun with the figures already included in Poser. (and daz figures as well)  I agree with the idea of making your own characters, thats what is nice about the dev figures included in Poser. You can do what you want with them, where as most other figures you cannot (except Antonia she's open source too) You can change them to suit your needs and rig them any way you want.  Dr. Geep and PilC have alot of usefull tutorials on many operations for Poser and figure creation.

www.drgeep.com/         www.philc.net/   Antonia:  sites.google.com/site/antoniapolygon/