RE: I need a report that extracts Customers' First and Last Name, as well as Department and/or Category they purchased from.

You may want to look here first, find one that closely resembles your needs and open a service request or contact a Microsoft Partner to modify an existing RMS report for you or tell us which report it is and what you'd like added and we'll see how that works out.

mbs.microsoft.com/.../modifiedreports_rmsstoreoperationsreports                     

Hope that helps you, enjoy your day.