I don't really know if i can help further. I am not at all expert with the terminal and I stopped using the Sony a while back in favor of a Touch and then an iPad.
I just followed Beartard's guide above. Carma54's last post puts it in more detail, although her points 5 and 6 can look a little confusing. #5 ends with "jpg". Do not type "to remove the song..." Likewise # 6 ends with "images/
This is all assuming you use a Mac. I'm sure there's a way to do this on a Windows machine, but I know nothing about them.
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I almost forgot: libprs500 is now called Calibre. There is information here--in the manual--about installing command line tools:
http://calibre-ebook.com/user_manual...command%20line