How Do I Add Value To My Leads?

I’m launching a trial product soon. I’m trying to figure out how to add more value to my paying leads and partial leads, like CPA networks do.
Are there any sites that would pay me if my leads subscribe to different related email campaigns?
Also, how would I find other related products that I could offer my leads to sign up for while signing up for my product as a type of "combination" offer?

If any affiliate/cpa network managers read this and think your network will allow for these type of things, please feel free to contact me.

See original post by sethuhdiah