I totally agree with you. I would love to meet some non-technical people who have practical experience. However, most of my friends are technical and I don't even know where to start looking.
That's where the networking comes into play. Going to business meetups. You can meet seasoned entrepreneurs in the local business community who would love to cross into something more technical, but don't know how.
This can end up being quite awkward. You end up being the 'belle of the ball' and end up having to weed through a _lot_ of, well, not so great ideas. Remember when everyone had their own idea about the 'uber of x'? That.
I can't speak from experience (or I'd have my own startup) but I think the best non-technical cofounder is found while working a technical job with someone of like mind. Or at Uni it seems.
A disciplined sort of triage can work for this. First, do they have real business experience? Ideally, have they started successful businesses before? A lot of the learning curve of startups is the learning curve of just being an entrepreneur.
Also, does their idea make intuitive sense to you, especially in terms of how can this be monetized? Vague, handwavy social apps that don't charge directly are a common problem. Apps for customers who don't have money is another popular antipattern. Apps that seem trivial are generally bad. Apps that respond Boolean true to "Can I already do this with Yelp?" are toxic.
But you find someone who has a couple of businesses already under their belt, who has some specific customers in mind who have a specific problem that person already understands... then you're getting somewhere. And it may be an entirely unsexy problem. One of my favorite startups locally is a company that has built a system for detecting excessive water use/leakage in toilets - something that can be repaired at cost savings if you have a large building (say, apartment complexes). Totally unsexy. Great market.
I don't go to too many networking events but would be keen to grab a coffee. Not ready to start my next thing again but learning to code and have more than a few ideas up my sleeve.
