Q. I have a Sony VAIO running Windows Vista and a Mac laptop. I have an iTunes library on both computers but want to transfer all songs from the Sony to the Mac iTunes library. How is this done? - Michael
A. There are a few details related to your question that can have an impact on my recommendations, so I will see if I can cover the most common scenarios.
If the iTunes libraries are completely different, then moving the files from the Windows system to your Mac library is pretty straightforward. You can use any form of storage to transfer, depending upon the size of the library, including CD/DVDs, flash drives, external hard drives or even your iPod or iPhone.
If, however, both libraries have some of the same songs, you will want to be a little more particular about what you transfer so you don't end up with duplicates throughout your library.
Another variable is whether you are transferring purchased music that you manually added via CDs to your Windows iTunes library. Purchased songs from the Windows system need to be authorized on the Mac system after they are transferred in order for them to play (you simply enter your Apple ID and password the first time you play the song).
You can authorize up to five computers to play your purchased music, so if you don't plan to ever listen to the songs on your Windows system again, be sure to deauthorize the songs. Click on the "Store" menu, then on "Deauthorize Computer" in iTunes 8. Older versions have it under the "Advanced" menu instead of "Store."
Another consideration is whether you want to transfer your playlists, ratings and play counts along with the music. Manual copying will not transfer these items in their entirety, so this is where using an external hard drive or your iPod or iPhone as an external hard drive is a good choice.
Apple has a detailed, step-by-step resource that will walk you through using an iPod (or an iPhone or any external hard drive) to transfer your music, playlists, ratings and play counts from one computer to another at http://bit.ly/WcSv5.
If your intent is to keep using iTunes on both systems, there are a number of resources you can consider that would allow you to "share" your library across your local network or via some Web-based services.
ITunes itself has an option that will allow you to share your library with other computers on your network. For this to work, iTunes must be running, and you must tell iTunes you want to share some or all of your music (Edit, Preferences then click on the Sharing tab to change the settings).
If you really want to extend your ability to share your music library (let's say between home and the office), you can install a program such as SimplifyMedia (http://www.simplifymedia.com), which is free.
Not only can you share the songs with your other computers anywhere on the Internet, you can also share them with your iPhone as long as you have a decently fast connection to support the stream.
Finally, if you want to keep your libraries synchronized across multiple computers on an ongoing basis, you can buy programs such as SuperSync (http://supersync.com). You can try out SuperSync before you buy it as well.
Caution: Because this is the most ambitious approach, it has the most complexities, which means it has more points of failure. Before using any kind of iTunes syncing program, be sure to back up all of your music libraries first.
Ken Colburn is president of Data Doctors Computer Services and host of the "Computer Corner" radio show, which can be heard at noon Saturdays on KTAR (92.3 FM) or www.datadoctors.com/radio. Readers can send questions to email@example.com.