Thanks for the help.
The 650 was working. The sony library wouldn't detect the device, just the little black device icon that used to say "reader" now says "error" so I tryed rebooting the computer. (I don't know if that counts as disconnecting with out ejecting the device??) but I did it anyways. Started up Sony library again, it still did the same thing and I couldn't even close the program. I had to Ctrl+Alt+Del and end it in the windows task manager. I am using Windows 7 by the way.
So I uninstalled sony library (this is the first time I will try to reinstall it)
(first, I saved all my books to a different file and to Adobe Digital Editions just to make sure I don't loose the books.)
Then I have uninstalled Sony Library (using Revo Uninstaller) and reformated my 650 (using settings -> initialization -> format memory -> internal memory) So now I will try reloading the sony library.
Wish me luck. I'll let you know how it goes.