How do I retrieve notes for past daily re-occuring meetings when .

Basically, I used a regular appointment, every day, as a means of keeping a
written diary or journal. I wrote three or foour paragraphs every day from
early July 2004 to Sunday 19 December. On the Monday I thought I'd better
extend the meeting spots on my calendar into 2005. So I opened the series of
the meetings, hit the recurrence tab in Monday and the extended the end date
until 31 December 2005. I then hit the save and close, it then asked me if I
did want to save the changes, I agreed "yes"!

To my horror the next day, not only had it saved the recurrence changes but
it saved a blank page to all the past meetings with my three or four
paragraphs each day for five months and effectively deleted all my work.

How can I retrieve my work?