What goods are you expecting?
Well, the "traditional" hope is that micro-gravity will prove a great environment for growing super pure crystals. (The last I checked into this area, there were conflicting studies indicating that very high gravity might be better for pure crystal growth...)
As more and more circuitry can be compiled onto super-pure crystals, entire machines can be fabricated in clean rooms. And, as nano-technology becomes a real deal, entire mechanism can be built in clean rooms.
If the raw materials for such stuff -- basically "sand" -- can be lifted off the Moon, or cobbled off asteroids, then an entire "Silicon Valley" could be constructed at, say, Lagrange 5 and would have the entire globe -- heck, the entire inner system! -- for a market...
Mark W.