Yes it's a 3D application that came out around the same time Character Studio Max came out... I'm not sure on it's relevant usability in the industry now a days but I'd start learning Maya if I were you... every company is starting to turn towards Maya. Great for game platforms and Visual Effects.
I'm pretty sure Rhino was just intended as a modeling program for an alternative to using Lightwave's and 3d Max's modeler programs (it could export to tons of different programs for surfacing and animation, not sure on import though). I always heard it was a pretty decent modeling interface though some people liked it better and some didn't.
I still think modeling in Maya is a pain in the rear though.
Draw it as stroked arcs. Pathfinder does far more than connect or unite shapes. It also divides, crops and cuts with a mask. You want to divide everything then unite back together the bits so it looks...