I agree with planb77.
-make a new folder on your desktop called sync to ipod.
-copy your photos into that folder
In iTunes when your iPod is connected click on it under devices on the left.
This opens the summary
-click the photo tab at the top
-make sure there is a check next to sync photos
-in the drop down section select choose folder, this opens a new window
-navigate to your desktop and click on your sync to ipod folder
-click choose folder or ok on the bottom right
-click apply then sync on the bottom right.
That will get them on the iPod.
Now when you want to add or remove photos from your ipod, just change the contents of the folder on your desktop and sync through the photos tab again.
Hope this helps.