I would need a clarification of an iTunes feature "Add folder to Library" (without automatic copying of media files to the default iTunes folder). I know this adds all media files from the selected ("external") folder to the Library, and uploads them to iPad upon sync. However, does this also mean that any changes to the folder that was added this way, will result in subsequent changes to the Library (and, in turn, iPad) as well? E.g. if you add or delete a song to/from such ("external") folder (within Windows 7 file system), will such change also result in automatic removal/addition of the songs from/to the library (and, in turn, iPad)?
Or is "Add folder to Library" a one-time activity only?
One more thing... is there some sort of (over)view where you can see which ("external") folders have been added to the Library?
The short answer is no ... with a caveat. When you add a folder (and its contents) iTunes - IF you have iTunes set up this way - iTunes will make a copy of the files within the folder and save them to its own database. So, after upload, you can delete the folder and it's content.
This is the way I keep my iTunes set up as its the only program that I use on my computer to manage my media files. To make iTunes do this: in iTunes, go to Edit > Preferences > Advanced and check the box that reads "Copy files to iTunes Media folder when adding to library." I find this to be the easiest way to keep my media sorted as it's all in one place. Of course and as always, YMMV.
Using this method will make it so the new files are seamlessly blended into iTunes; they won't be in separate folders within iTunes. So, no, with this set-up, you won't be able to tell [later] what folders have been added to iTunes (though you will be able to see if the media has been added). And, it will be a one-time deal; once you've added it to iTunes, it's there until you choose to delete it from within iTunes.
Since I have my iTunes set up this way, I can not tell you what happens with the folder and iTunes if you move/delete the folder after upload if you don't do my method. I believe iTunes makes a link to the folder - in which case, it probably wouldn't work if you moved or deleted the folder (iTunes would not be able to find it or it's stored media). All I can suggest here is to try a test on a single file
Regardless, after you've uploaded the folder and its contents, it's still a manual operation for moving the media to the iPad; you've still got to check that media (whether in a playlist or individually) in order for iTunes to sync it to the iPad. iTunes will not automatically add that media to the iPad - that's up to you.
And, regardless of how you got the media to iTunes, if it's not checked to be synced with the iPad and it's already on the iPad - yes, it will get removed from the iPad on the next sync. Cause, remember, iTunes makes the iPad match what you've set. It will add or delete media based on those check marks you've used.
Hope some of this helps. Holler back if I've confused the issue or didn't answer your question?
Marilyn
