I'm loving the new milestones portion of Freelancer, it allows us to do exactly what you are asking for without a major commitment or major letdown on either side.
First, you're looking for someone who speaks English well. I'm a native English language, and wish I could say I speak other languages, but sadly, English is it for me.
Second, you've got a long term idea. We're approaching my busy season at my day job, but I've got nights to discuss project ideas, and if this is a long term idea, perhaps we'll time it just right so we can start rolling when I'm not as busy.
Last, I'm a patient guy. I do want something to be in it for me in the end. So while I am happy to start a discussion about what you're looking for, at some point, if we are going to proceed, we'll need to re-evaluate our business relationship. Whether that involves ownership stake discussions, or simply re-evaluating the fee for service, or deciding that there's really nothing to proceed with, at some point, we'll need to re-evaluate - for the long term.
With that, I propose we start with some milestones as I outline them, and if at any time we wish to sever the relationship, we're not out anything overly large.
Hope that works for you, and thanks for looking.