Well guys I think I've got a decent spreadsheet going now, use this URL to view it:

http://spreadsheets.google.com/ccc?k...oKvbbHZKXI7aJg

and this URL to access a convenient form to fill out and add a data point for us!:

http://spreadsheets.google.com/viewf...oKvbbHZKXI7aJg

Also here's a link to a summary page:

http://spreadsheets.google.com/gform...gridId=0#chart