My first question would be to ask you where you are located? Not sure if you want to reveal a specific city or not. Where you are matters.
"The business people I am in contact with are already busy with their own things."
True. Which is why you need to be somewhere where there is a chance of meeting people who are in between, recently graduated etc. There is also the possibility of someone who is employed full time starting to help and give advice on the side. When/if the venture takes off they would feel more secure in leaving their permanent job.
"it seems like a good business person will always be busy doing their own businesses, as that is what business people do."
You only need to find one person (it's like getting married). There are of course compatibility issues as well to consider.
"have much interest in building it if I'm also going to be responsible for selling it."
If you build it and it makes sense from a business perspective and have a prototype you can attract that one or two people you need. With just an idea of course you can't. Care to elaborate on the idea at all?
