The gap between art and engineering is usually filled with an Industrial Designer. I think that is the type of work you are describing, although ID encompasses more than just 3d modeling.

I do ID for a large door hardware company, working with engineers and marketing. The standard 3d software for the industry that I see in job postings are: solidworks, pro-e, alias or Rhino. I use Moi since I run the studio and want to focus more on creativity and exploring different concepts than getting too worried with technical details (I let the engineers have fun with that)

But I think what is important about software is knowing theory. Generally if you understand 3d theory (nurbs, poly, etc...) then you can learn whatever software might be required at whatever company.

Check out coroflot, which is a place you can post portfolios and browse jobs.