Q: Where do I find Serial Number for FCP 6

Thanks for that.   As I originally thought,   I have lost, to me, a valuable tool.   As  a last resort I will endeavour to raise Apple to get it to look into its own records for my sake.

As a vdry last resort I will go through all my stuff from AS 1900 and see what I find in the way of serial numbers.

Thanks to everyone who replied.

I found the serial number.   FCP6 now up and running.  Viola.   Sorry about the very late return/reply. 

Thanks for the interest shown by those concerned.

Ron