iTunes library and original files that were imported?

I am in the process of having a clean up of the MacBook in preparation for the arrival of my new Apple TV

As I am going to be converting a number of movie files etc I wanted to clear some space, and noticed that I have all of my downloaded albums in the following;

users/mike/music/albums

Here they are stored by album name within folders. This was the source for importing to iTunes.

I also seem to have the same in the following;

users/mike/music/itunes/itunes music

Here they are stored by artist.

My question is, can I delete (or backup and remove) the downloaded files and folders without losing the file from my iTunes library? If I can do this it would clean up a lot of space on my drive.


Secondly....

I have AirPort extreme. Can I have a USB drive attached to it, and have the library on there rather than on the MacBook? What are the pros and cons of doing this if it is possible. I have a thought that to use AppleTV I would need the MacBook on anyway so potentially as well leaving it where it is?

Hopefully once I get an understanding of the above, I can start to use iTunes smarter and better to enjoy it and Apple TV more!

Many thanks
Mike

users/mike/music/itunes/itunes music is the default location.
Unless you changed it, that is where iTunes goes for media. You can double check this here: iTunes (menu) > preferences > advanced.... It will show you the path. (and let you change if you want to move your stuff to an external drive for example)

Any other media on your computer not in the above location is not part of the iTunes library.
If you were to go to iTunes > File > Add to library.... then select some audio files not in the above location it would copy them into the proper location, leaving duplicates where they originally lived.
You can put it on an external drive (I have a 500gb drive just for my iTunes media) but I don't know about accessing it via the AEBS.

so by that, I can remove files that are not in default, as iTunes doesn't refer to them anyway? Then if I move the iTunes library to an external HDD then I just update the path to the new location?

Thanks for the quick reply

You can remove files not in the iTunes library (see above to positively ID your iTunes library) if they're already showing up in iTunes and you don't need them otherwise.
If you move your library just hold down the option key while you launch iTunes and it will prompt you to pick your library.

on a side note... is this the same logic for iPhoto?

Yes, same idea as iPhoto.
BTW go to iTunes (menu) > preferences > advanced.... and make sure the "copy files to iTunes Media folder when adding to library" box is checked. It's checked by default but it needs to be checked so it behaves as I described above.