You could write a script that uses the export container field contents step and loop through all your records to get the images. This can be used to save all of the images to your desktop or whatever path you setup
I know of no way to export images to an excel file. Is it possible to set up a file reference to the image file in Excel? If so it might be possible to export text to a column in the excel file that can be used as a reference to the image files Mark suggest you export. Export Field Contents can be used to name the exported file so you can use data in your table to name the exported files in predictable way so that you can then also export the correct info for the file reference in Excel.
But all of this assumes that this is even possible and I don't konw if it is or not.
Yes, I think the best you could do is export the file path for the image, if it is stored as reference in the filemaker file. If the images are not stored as reference you could export them to a folder, reinsert them as a reference either into the same container field or a second one and use that reference to get the file path to the image. Then export that file path to the excel file.
I haven't worked much with Excel and don't know if it is possible to have it display an image from a file path or a link. Maybe its possible to write a macro in Excel that would then take that file path and insert the image?
You can also determine the path and file name for the exported container field and put that info in a field for export instead of re-inserting the file into a container field.