1. WHo are you? Your site says nothing about you. I'm going to give you the keys to the PHI kingdom, I need to know who's soliciting me. Are you two twenty-somethings with amazing skills and ideas, or 20 ex-Epic employees looking to fill a particular gap you found? Without this general information I wouldn't know what sort of project to think about including you in.
2. Where are you? I'm under contract with numerous health agencies that require data to be on US soil. I have no idea if you are in Romania or Virginia. (Side note, government is the biggest purchaser of health care and therefore your paths will cross at some point, even if it's simply being downstream of federal or state data.)
3. How compliant are you? Your one page tells me nothing about your understanding of HIPAA, nor how you ensure the security and privacy of the data you will be exposed to. It may seem as if anyone in the space _should_ know about this and the reader can assume compliance, but frankly it's not the case. Yell at me about your third-party audits, your ability to transact PHI, as well as any SOC/FISMA compliance you have.
4. What have you done before? There are a lot of corners in the niche, and I'd need to know what systems you've worked with, what you've built and who for, so I can get an understanding of whether or not you'd be a good fit.
As for leads, with most conferences going virtual your usual approach of HIMSS is buggered, but Healthcare Datapalooza just put out a call for presentations so they're likely looking for (virtual) sponsors already. I assume HIMSS and HCDP sell attendee data, have you looked in to that? And how about FHIR aggregators like 1up and Redox, they are likely plugged in to many of your potential customers.
I'd be happy to chat more, my profile has an E-mail address you can use. Good luck with your venture!
EDIT - forgot to mention, starting out a great way to get noticed is to participate on a HIT Challenge, not sure what's up for grabs lately but challenge.gov - easy way to find the right people to start netowrking with.