If you want to run a report to see all the "Notes" entered on a Client or Project then run the Client Project Entries report. From there you can choose a specific date range to/from and filter either by Client or Project.
If you only want to see the "Notes" you can uncheck the Client File Uploads, Expense Entries, Time Entries, and Project File Uploads. Click Update when finished choosing the filters you want.
From all the reports you can Print, create a PDF, and export to Excel.