Once you've decided on a program, let us know, I'll do what I can to find some tuts for you. Just as an example of how it's the artist and not the tool: I started modeling in Rhino, a NURBS based program, making creatures/animals. I then tried MAX for the same purpose, dabbled in Lightwave making creatures and abused WINGS to the same end. I now use Softimage XSI and SILO3D. That's a wide range of programs and interfaces, some touted as being more "organic" than others but in my experience, it's really not the program. It's the artist. I think, with your traditional art talent, you'd pick up modeling creatures in no time at all, as long as the program you use has an interface you like. So, like most of us have said, try out the various programs and get back to us once you find one you like. We're here to help but we can't tell you what will work best for you.