Log in to Myspace. Note that you must have a music artist account on Myspace Music to upload songs from your computer. If you do not have an artist account, you will need to create one.
Position your mouse cursor over the "My Stuff" tab on the top of your profile screen. A menu will open offering you choices.
Place your cursor over "Upload" in the third column under the word "Songs" and click once. Another window will open with a list of songs currently in your playlist, if any.
Click on the blue "Upload Songs" button in the upper-right corner and on the blue "Find Songs" button that appears in the center screen.
Find your folder that contains your WMA music files in the computer file search window that opens. Optionally, you may simply type the name of the song in the search box and your computer will locate it for you.
Click on the song you wish to upload and click "Open" once. Your song will start the upload process and will show in your Myspace player when completed.