Lost USB Storage Device

I keep a lot of my confidential bank details, bank balances, passwords,
customer account details, etc stored on a USB storage device. I prefer not
to keep them stored on my laptop for security reasons but ironically I have
lost my USB device and I fear I am going to have to make a good many calls
and letters to retrieve this information.



On my laptop I edited the excel file, that contains my data, only hours
before losing it. Does a pc keep a temporary copy of the file that I could
retrieve?



I would happily buy some un-delete software if the data can be retrieved. I
have made a point of not using the pc since knowing the USB device has been
lost so as not to possibly overwrite any temporary information.



Thank you