You are not alone,
rebarnmom. I've never had probems with the Sony Library and I find the way Calibre creates folders for each author and book annoying (I prefer all my books to be in one big directory), plus the UI of Calibre is confusing and non-standard.
The Sony Store is all right, but I get most of my books direct from publisher sites (e.g.
www.loose-id.com) or resellers like OmniLit.
You can check out the sticky thread,
E-book sources beyond CONNECT for more e-book stores. The Sony Store used to be called "Connect" and the thread title's never been updated.