Personally speaking, I use AirDroid
. You load it onto your phone, open the app, go to your computer and open the web site that it tells you to open on your phone. You would then just transfer the music to your phone (and any other media for that matter) via your web browser.
Or get an SDCard and an USB SDCard reader, copy the files over to the SDCard, and then put the SDCard into your phone.
In the Android world, your music is just that... files. Plain simple files. Put them anywhere you like on the SDCard. Personally, I put them all into a folder called "music" and the Android Media Scanning service will find them and will populate your media player app on the phone with the music.
Plain and simple. No iTunes needed. Thank God.