Greetings Lord Iain
Mistress Arianna has covered all of the basses (LOL) for the starting of the organizing for the Choir.
Since you were asked by your Crown to organize the choir, you may want to see if they have any requests.
It is the Mission of the Known world Choir to open people to the singing and learning of renaissance polyphonic vocal music. that being said, you need to get the music to fit into the time frame that you've been given. If you have the chance to prepare learning tracks, you can do more music. (idealy)
Start with the practice and performance details. find out where your practice space will be and how many days/hours per day you can have to practice. Perhaps co-ordinate with the "Noon time" singing that happens.
It is our goal to have the website up and running by the end of the calendar year. You could host the learning tracks and music on the site. For now, you are welcome to use the yahoo groups to host your music and learning tracks.
I have found that very helpful.
good luck and don't hesitate to ask questions!!