Hello & welcome to MR.
Check out the eBook library from MR
. Sooooo many free books, lovingly formatted by MR members. That'll keep you reading for a while.
A lot of people don't like the software coming with the Sony. Here is a good alternative: Calibre
. Very easy to use and it allows you to organise your books exactly the way you want.
And don't forget to look into the Lounge
if you want some fun.