iSyncr is actually two apps; one for your phone, and one for your computer. Just download the app from the Android Market, and when you first start it up, you can install the PC or Mac executable on your device's SD card (no installation on your computer necessary). Then just plug your phone into your computer, start up the app, pick the playlists you want to sync and let it go. It works with any music app on your phone, will sync iTunes' album art and can even sync over Wi-Fi instead of USB (though you'll need this add-on to do so, and it currently only works for the PC version). Honestly, we're not sure it gets much simpler than this — if you use iTunes, this app is a must-have.
iSyncr is a $US2.99 download for Android devices, works with Windows and Mac machines running iTunes. There are free versions available, but they only sync 20 tracks at a time and are thus more "trial" versions than anything. Hit the link to check it out, or scan one of the QR codes below to download it straight from the Market.
PC QR Code:
Mac QR Code: