One reason may be that you're putting the cart before the horse ... as far as I can see.
Your fellow JVNP partners that have made good use of this community have first introduced themselves, posted a profile about themselves and what their business is about in the appropriate category, and taken the time to ask questions and provide answers when possible to help build their credibility, self brand, gain trust and respect ... they let valuable content get folks interested, and allow their sig file to give partners a way to find out more without looking like they are desperate ... or only out for themselves.
I'm not one to believe that learning Online Business, Internet Marketing, and JV Marketing should occur at the same time ... you should have a firm grasp of what it takes to make money Online before you venture into JVs, IMHO. That way, you have something to bring to the table.
A few of the exceptions may be if you're an established software developer, graphic artist, webmaster/author, or you specialize in an area that would be of benefit to an established Online Marketer ... (even if it is simply interviewing established Marketers in a specific niche to create a product ... though you'd still have to have it in a Marketable state when bringing it to the prospective partner) and you negotiate a deal to allow them to either split commission or have co author rights in return for their Marketing ability.
If that isn't the case, you'll have to work on building your self brand, Marketing system, email list, and how your offerings are perceived (does your site and it's offerings represent you well, in terms of professionalism?). If you have a list, reach out to a partner you'd like to work with and become an affiliate ... sell a few of their products, and do what you can to get them to know you better (join their newsletters, interact on their blogs and in their forums, etc.). Qualify other partners into you mini Alliance, and you'll have the ability to cross promote each other ... using that leverage to grow faster as a group than you would have been able to do on your own, BUT ... truly successful JV Marketing starts with the first partner that reciprocates.