In addition, this builds trust that will be pivotal at getting your product in front of more people.
Do I email them just saying I want to talk about your business? Walk in and strike up a conversation? In the latter case I feel like I'm actively obstructing their ability to work and not sure about the former.
I like the idea, just not sure how to implement it
Showing up at their work is likely not going to get you what you want because their day is probably already scheduled and it could be a pretty big inconvenience. Or likely a major waste of your time. Let them schedule through email. I'd be willing to bed if you get 10 - 20 email address or companies, you'd get a couple responses agreeing to a phone call or company.
Make your first interaction short (5 - 10 mins) and work to develop that relationship as they could maybe even become your first customer.