Sam,
Is this your first time to do such a task? If so how familiar are you with Cisco UC technologies as asking questions requires knowledge since questions lead to discussions and detailed descriptions of features and functionality is required. I have trained many engineers over the years and from my experience it is impossible to conduct decent discovery without very good understanding of the solution.
With that being said these types of documents are considered intellectual properly and I don't know how many folks will freely give these up, so you might want to consider building your own.
HTH,
Chris
