Not to be dense or anything, but I'm not sure what it is.
Is it an ebook?? A software program?? Is it a guided consulting program??
What reason do people have to pay you after a free trial?? What is this product going to do for them, and why should they pay for it if you're giving it to them on a free trial???
I think the reason you're not getting more response is that it's unclear exactly what you have, and I'm the only one brave/dumb enough to say "I'm stupid - what are you trying to sell??"
Maybe what you should think about, though, is a membership site. Convert the ebook to an online book and you can allow free access for a set period of time. After that, they are charged automatically once a month for continued access. (you can also give members the option of purchasing the ebook at a reduced rate after they join.)
As a twist on the above, instead of a free trial with the ebook in their hot little hands, you can give free access to the site for the free trial period - then if they want to purchase the ebook, they can.
Give us some more info, and I'm sure others will chime in....
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