I want to build/sell a product. Steps?
Todd: You should check out contract manufacturing. Many of these types of small jobs can be handled by a CM in China. The problem with any physical device is cost--cost in materials, machining, tool building, assembly, etc. This means you'll probably need to get some form of financing. You may be able to do a small run for not too much (10's of $k), depending on the device. This is why I always opt for bits over atoms these days.