I want my friends and contacts to claim chunks of work, and I'll pay them for their work after launch. I'm looking for advice on how to organize the work, for

I want my friends and contacts to claim chunks of work, and I'll pay them for their work after launch. I'm looking for advice on how to organize the work, for one -- if they were all developers, I'd set up a wiki, but I want something easier to annotate and edit for non-technical people.