The Text Import Wizard can replace existing data in a worksheet when it brings in new text. Use a blank worksheet so you don't risk overwriting your current data.

Rerun the Import Wizard, this time choosing to append data to your new table and specifying the name of the next file you want to import. Append your data and launch the wizard again for the next ...

PDF Data Connector from Microsoft will help you import and use PDF data into Microsoft Excel spreadsheets. Learn how to use it.