Are you looking for a rotisserie setup?
If you want to roast coffee, I would highly suggest you look into an RK Drum Roaster.
http://www.rkdrums.com/index.phpI have the older style 4 lb. Drum and 50 RPM hand built by Ron Kyle shortly before he passed away. The company still lives on and has some really nice products. They are a bit on the spendy side, but they are serious hardware. I've lost track of how much coffee I've roasted on mine (over 500 lbs and counting).
A lot of commercial roasters got their start on hotrod Drum Rosters. I've not roasted nuts or Cacao (yet) but these units will get the job done.
There are lesser quality units out there, and I'm sure you could modify some of those countertop rotisserie tumble baskets that could work. The trick is to keep them moving at a higher speed than BBQ rotis motors.
As far as pans for roasting nuts, I use those square perforated grill baskets with the angled sides. I can fit 3 of them in my Cookshack or 22" WSM with a raised grate or Stacker. @ 1lb each is ideal.
When my daughter was in JHS she did a presentation on coffee growing and processing, found a charity that assisted Rwandan villagers coffee efforts, we bought their Green Beans, roasted them and sold them through her school and donated everything back. It was very successful, the coffee was really good and the teachers, parents and kids dug it.