well you can talk to the website, which rules out a firewall block possibly. it could be a bad DNS entry
when you type
ping feedbooks.com
make sure the IP address is the same as above.
it should look like this
I'm hoping that's what the problem is, cause that will be easy to fix.
if the IP address IS right when you ping feedbooks.com
if you could extract firefox portable to your desktop, and run it and try to go to feed books, that would rule out a browser problem.
http://portableapps.com/apps/internet/firefox_portable
to remove firefox portable from your computer, just delete the folder
Let us know what happens