If you used Amazon's Send to Kindle and you order a new device you'll be able to easily download all that stuff from the Kindle or send it to the new Kindle 10 items at a time from Amazon's Manage Your Content page.
If you've copied from your computer to the Kindle via USB you can simply copy it back to the PC (assuming you don't have a copy there already) and copy it to your new Paperwhite.
Barry
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