Welcome to the forum lionel47, and congrats on the reader. Be sure and check out all the free books here at mobileread
https://www.mobileread.com/forums/forumdisplay.php?f=126 that are ready to go for your Sony. You can also look a few forums down from that one and get many ePub books that will also work..... And here is a like to free ebooks from the Sony store
http://ebooks.addall.com/sonyfree.html . Be sure to check back on the Sony link as the book content changes. Also Kobo
http://www.kobobooks.com/ is a good place to buy books and often cheaper than Sony.
I do not use the Sony software myself, only use Calibre...
Again, congrats and have fun!
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