There are a few different ways that you can go about finding workbooks that contain macros in Excel. One way is to use the Find feature. To do this, open the workbook that you want to search and press Ctrl+F. In the Find and Replace dialog box, click the Options button. Make sure the Look in: drop-down menu is set to Workbook. Then, in the Find what: text box, type .xlsm. This will search for all files with the .xlsm extension, which are the files that can contain macros. Finally, click the Find All button.

Another way to find workbooks containing macros is to use Excel's built-in macro recorder. To do this, open the workbook that you want to search and press Alt+F8. This will open the Macro dialog box. In the Macro dialog box, click the .xlsm file type and then click the Search button. This will search your computer for all files with the .xlsm extension.

You can also use a third-party file search tool like Everything. To do this, download and install Everything from https://www.voidtools.com/. Once it's installed, open Everything and type .xlsm into the search box. This will search your entire computer for all files with the .xlsm extension.