[mamcx]

Let's imagine that not all the advertisers are that shady, and just don't know better. Or if I wish to serve a subset of them, how break into this business? How get the first batch of customers?

I have some ideas about build a server-side ad-network, but because I imagine is very hard to get customers I dismiss it, for the same reason: You need to be "famous/large" to attract customer in the ad-space.

[geocar]

Well, who do you think your customers are?

Publishers want someone to handle monetisation of their website. If they get enough traffic, they want that someone to work in-house, but if they don't, they want some one (ad network) to do it for them.

Advertisers want impressions/clicks/performance.

A (successful) ad network needs to do both, so bootstrapping invariably looks something like matchmaking in the very beginning.

If you want to find my email address and reach out, I'm happy to talk to you more about bootstrapping: I've gotten more than one ad network off the ground.

[mamcx]

I follow the links in the hn account and don't see the email.

Mine are at http://elmalabarista.com

[coldpie]

Some exist already, you may gain inspiration from them. Project Wonderful is one I know about. There was some guy on here a year ago claiming to have an ethical ad network, but when I visited his client sites, it was mostly "Click Here to win a Free iPod" scams. I think you're right, it'd take a lot of work to find both clients and advertisers interested in working with you given your ethics-inspired limitations.

Edit: The other problem you'll run into is the tragedy issue I mentioned. Your ads will be blocked by most ad-blockers' scorched-Earth policy, which comes from your shitty, unethical competitors. Good luck to ya ;)