Aggregate spreadsheets

I have a simple job, and need it done urgently. The following website has a spreadsheet that can be downloaded: [login to view URL] The spreadsheet corresponds to data for 16 Sept 2009 (hence the numbers at the end of the web address). What I need to do is download each spreadsheet from this day, up to 31 March 2010 - and to aggregate the files download into one big spreadsheet. The consolidated spreadsheet needs to have a new column in it that contains the date of the data concerned. If the data is too big to fit into one spreadsheet (you might run out of rows) then either: place it in separate sheets. Then, I need to do the same thing again (same dates) with the following spreadsheet: [login to view URL] NOTE: IN THIS ONE THE FORMAT CHANGES ON 30 JAN 2010. From that date forward the spreadsheet has more columns. So please provide one file for the dates 16 Sept 2009-29 Jan 2010; and a second file for the dates 30 Jan 2010-31 March 2010 This needs to be done perfectly, with no errors!