You can sync your Samsung Galaxy S smartphone with iTunes, using third-party software designed to enable synchronization capabilities for non-Apple devices. As of June 2011, the iTunes music management software is designed to only sync with Apple devices like the iPod and iPhone. You can circumvent this with software that spoofs the user agent of an Apple device, enabling you to transfer your music files to any device you'd like, including the Samsung Galaxy S.
Download and install the iTunes Agent software from ita.sourceforge.net.
Connect the Galaxy S to your computer using the appropriate USB cable.
Slide down the Android notification drawer once the device is connected to your computer and select "USB Connected," then tap "Mount."
Click "Start," then "Computer" and double-click the Galaxy S device icon.
Click "File" and select "New," then "Folder." Type "Music" as the name for the folder.
Right-click the iTunes Agent notification icon located beside the clock in the system tray, and select "Preferences."
Click the "New" button.
Type "Galaxy S" as the name of the device and select "iTunes" from the "Synchronization Pattern" drop-down menu.
Click the "Choose" button beside the "Music folder" text box and select the "Music" folder you created earlier as the destination for synced files.
Click the "Create" button beside the "Recognize by folder/file" text box, and again select the "Music" folder you created earlier.
Click "Save," and then click "Close."
Click "Start," type "iTunes" in the search box at the bottom of the menu, then press "Enter."
Click the triangle beside the "My Devices" folder in the "Playlists" section of the iTunes sidebar to display the "Galaxy S" playlist option.
Drag and drop music that you want to sync to your Galaxy S from the iTunes library to the Galaxy S playlist.
Right-click the iTunes Agent notification icon in the system tray and select "Synchronize devices" to sync your Galaxy S with iTunes.