amateur design consultant?

Could anyone give me a suggestion of good airplane design consultant
with a reasonable service charge for light/sport airplane conceptual
design? A professional design agency would be great, but I believe a
graduate student in aeronautical engineering should be able to help me
out.

I am not an engineer and only have private pilot's paper test level
aeronautical knowledge(don't sneer at me. I passed the test in the
first try!), but I am now just fascinated with the idea of designing
and building and yes, flying my own airplane! I am brainstorming a
twin 3/4 seat camper design using two Rotax 912S or Jabiru 3300 with
reliability(twin), simplicity(tube and fabric?), ruggedness(tube and
fabric and STOL), comfortability(large cabin for two sleeping)and low
cost in mind. I know I probably wouldn't have enough money and time to
build it anytime soon, but I just can't wait for proving the design
and seeing the airplane layed out on the blue print!

So now my goal is to get to the first stage: the conceptual and
preliminary design. Then I will save money for structure design and
stability analysis etc. Finally I hope I can have the construction
plan and then from there I can build the plane piece by piece over
time.

I know nowadays such light airplane design could be totally done on a
computer and there're some dirty cheap entry-level airplane design CAD
softwares I can play with, but these softwares do need human input
with sufficient aeronautical knowledge even though they look like a
dummy's software for those enginners who operate 150K REAL airplane
design CAD systems. So is there anyone good at any of those softwares
like AirplanePDQ or even X-Plane PlaneMaker who would like to help me?

Thank you in advance.

Shin Gou