I am new to Mac and my MacBook Air is full so it cannot finish downloading all the tv show series I purchased from Itunes so I want them to download onto my external hard drive. PLEASE HELP
MacBook Air, OS X Mountain Lion (10.8.5)
You can start savng whatever media you download from this point on to a different location but you don't really want to split your media to several locations. This can be done but may present problems in the future. Some people opt to move their entire iTunes library to an external drive. Some people opt to move just media to an external drive but keep their main library files on their computer. Unless you have a particular reason to do this it is usually best to relocate the whole library.
What do I mean when I say media and library files?
What are the iTunes library files? - http://support.apple.com/kb/HT1660
More on iTunes library files and what they do - http://en.wikipedia.org/wiki/ITunes#Media_management
What are all those iTunes files? - http://www.macworld.com/article/139974/2009/04/itunes_files.html
Where are my iTunes files located? - http://support.apple.com/kb/ht1391
iTunes 9 [and later]: Understanding iTunes Media Organization - http://support.apple.com/kb/ht3847
How to relocate your entire library.
iTunes: How to move [or copy] your music [library] to a new computer [or another drive] - http://support.apple.com/kb/HT4527 - a somewhat bewildering and not always easily understandable set of options.
Quick answer if you use iTunes' default preferences settings: Copy the entire iTunes folder (and in doing so all its subfolders and files) intact to the other drive. Open iTunes and immediately hold down the Option (alt) key (shift on Windows), then guide it to the iTunes Library.itl file in the moved iTunes folder.
For the record there's this reference for iTunes 11 but it really doesn't strike me as having the specifics you need. iTunes 11 for Mac: Move your library to another computer - http://support.apple.com/kb/PH12168
If you put it in the default location of Macintosh HD > Users > *User Name* > Music then you don't even need to start with the option key held down, iTunes will automatically look for it there. (Make sure there isn't anything already in the iTunes folder there that you want to keep since you will be replacing it with the one you are moving.)
Putting only media on a different drive
iTunes for Mac: Moving your iTunes Media folder - http://support.apple.com/kb/HT1449
Redirecting media downlods from this point on
Do as in Moving Your iTunes Media Folder but do not consolidate/organize to a differnt location. Just change the setting where you want media files placed.
You do have a backup drive don't you? At some point that external drive will fail and your library will be gone.
how to have all your downloaded items go straight to an external hard drive
