No offense intended, and perhaps you didn't intend for it to be interpreted this way, but the question betrays the same snobbery because it rules out non-established sites as link partners.
If you don't have your own network of websites to give PR to your new website, and you don't have colleagues who can do it for you, you can still acquire PR from established sites providing that your website has something useful to offer.
Not all websites have something useful to offer. Some websites are money machines, and that's fine. Nothing bad about that. However, if you want to have a money machine and PR, you have to have a network to seed it to get the ball rolling.
So I would suggest building some websites with something to offer then feeding your new sites with that to get the ball rolling. Yeah, it takes some work...