
Ultraportable  notebooks are finally fast enough that we can use them as our main  machines. But damn, the SSDs they pack are small—how are you supposed to  fit your entire music library on one of these? You're not.
Get  that music off your hard drive, bawse. First off, you can get a lot of  mileage out of streaming music services; there's no need to tote all 25  Air Supply albums around with you. But for the rest of your musical  needs—those Phish bootlegs and Marky Mark freestyle sessions—consider  getting your songs a second home.
First Things First: Get the Music off Your Old Computer
Say you just picked up one of those shiny 
new MacBook Airs that everyone loves—instead  of just migrating everything over from your old machine, be selective.  Before you do anything with your new computer, though, you need to get  your iTunes music library off your old computer. Luckily, doing that is  very simple. And these instructions work for Mac or PC.
 
 
Tell iTunes Where You Want to Dump Your Music
1)  Make sure your old computer is running the latest version of iTunes.  There shouldn't be an issue with loading a library from an older version  of iTunes to a newer one, but do it just to be safe.
2) You'll  want to create a new location for your default iTunes Music folder on  whichever external drive you plan to use. To do this, go to the menu bar  and click 
iTunes > Preferences....
3) From there, you want to click the 
Advanced tab. The first item in the list will be the iTunes Media Folder location.
4) Click the button to the right that says 
Change,  and either select a folder in your external harddrive that you'll want  to use, or create a new folder. Once you've selected a folder, click OK  to exit the preferences menu.
 
 
Then Dump Your Music
1) Once you've selected a new location for your music files, return to your music library.
2) From there, go back up to the menubar and click 
File > Library > Organize Library.
3) Check the box that says 
Consolidate Library and hit OK.
This  will begin the process of copying all your music files into one folder  (the one you previously designated) on your external hard drive.  Depending on how many songs you have, this could take a while.
Copy Your iTunes Database to an External Drive
You've  spent years rating songs and building playlists—don't give them up! To  make sure those musical memories aren't lost, you're gonna want to copy  over your iTunes library database from your old computer to your  external harddrive.
1) Go into your 
Music folder (where the iTunes folder is stored by default), or wherever you've decided store your iTunes library files.
2) There should be a folder simply named 
iTunes. If there are any music files in the folder (which would be found in 
iTunes > iTunes Media > Music), delete those files, but nothing else.
3) Then, drag/copy that folder to your external HDD in its entirety. Now you're ready to move to the new computer.
Now, What Are You going to Do With All That Music?
Now  you know how to offload your entire iTunes Library to an external  drive, but should it be a NAS or a standard drive? Or should you upload  to a cloud storage locker? There are pros and cons to each, depending on  how you live your life.
 
 
Option 1: Keep Your Music on a Standard External Drive
If  you're in lurve with iTunes, have a lot of Apple-DRM'd content,  actively manage an army of iOS devices, or just spend a lot of time  listening to music on your computer, importing your old iTunes database  onto your new computer and pulling your library from an external drive  is a great bet. It'll look like it's all right there on your machine,  just like the old days. That said, you have to plug into said hard drive  to get at your stuff.
But if you're the kind of cat who plugs  into a USB hub or a notebook doc when you're at home anyway, this  solution is perfect. Especially if you want the ability to sync your iOS  device without formatting it again, and be able to access all your old  ratings, playlists and playcounts. Here's how to do it:
1) If you've already installed iTunes, make sure it isn't running.
2) Locate the 
Music folder on your new computer. If you've already installed iTunes, there should be a folder named 
iTunes there. Delete it.
3) In a new window, locate the folder named 
iTunes you copied to your external HDD.
4) Copy that 
iTunes folder into your computer's 
Music folder.
5) Now it's time to open iTunes. Hold down the 
option key while launching iTunes.
6) iTunes will ask whether you want to create a library or choose a library. Select 
Choose library, then navigate to your 
Music folder, then your 
iTunes folder on your computer and double click 
iTunes Library.itl.
7)  If everything went according to plan, your music library should have  made smoothly made the transition to a new computer and external  harddrive.
But let's say there's music you know you'll want to  listen to when you're not connected to your drive—your work or studying  playlist, for example. You can actually set up a separate, smaller  library, and it won't get mixed up with your main megalibrary, either.  It's a little advanced, but you can handle it:
1) Hold down option when opening iTunes.
2) When asked if you want to Create a Library or Choose a Library, select Create Library.
3) Name the library whatever you want, but something logical like "Music on Laptop" probably makes sense.
4) Drag any music files you want from your external harddrive into the Music folder of your computer.
5) Once they've been copied over, drag those files into the iTunes app, where they will appear.
6)  Now you have a separate library of music stored locally. To switch back  to the library with the songs stored on your external drive, quit  iTunes, relaunch iTunes (while holding down the option key), elect to  choose which library you want to open, and find the iTunes library in  your Music folder you initially copied over to your laptop.
Option 2: Stream it From a NAS Drive
The  second thing you can do is to keep all your music on a NAS drive, which  means you can access files over your local network without having to  directly connect your computer to the drive.
This is great if you  have a lot of DLNA streaming devices like a Sonos system or Boxee Box.  And once you've offloaded your music from your old computer (follow the  same steps as above, just select the network-attached drive instead of a  USB-linked one), all you have to do is tell the device where to look on  the drive.
As far as working with iTunes, a NAS drive isn't  perfect for managing and syncing files to devices (it's sloooow), but  once you've imported your tracks into the library, it streams pretty  well, depending on the speed of your network. You can also get a NAS  that supports the iTunes server feature, where all your music will show  up in your local iTunes library as a streaming playlist.
Option 3: Stick it in the Cloud
If priority 
#1  for you is having your music accessible ANYWHERE you go, there's always  the cloud. There are currently only two services that are worth looking  into: Google Music and Amazon Cloud Drive.
Neither is perfect,  but they both more or less do what they say they'll do, which is make  your music available to you anywhere you go. You can stream in a browser  or an Android device, and if you want it locally, you can pull files  from the cloud. Each service uploads in its own way, but what the two  have in common is a particular disdain for your musical metadata.  Playcounts and ratings go out the window of the magical airship that  ferries your music to the firmament.
Also, if you suffer from  data caps or sucky bandwidth, the cloud will likely rain on your parade.  Furthermore, if you have a massive music library, storing large chunks  of music in the cloud can get costly. Amazon offers up 20, 50, 100, 200  and 500 gigabyte chunks of storage at a cost that breaks down to a  dollar per gig per year (ie, 50GB=$50/year). Google Music is still in  beta and working out its pricing.
So now you can rest easier  knowing you have three solid housing options for your music library now  that's it has moved out of your laptop. Which one you pick ultimately  comes down to your listening habits, but one thing is clear: a big  laptop hard drive is no longer a must.