127.0.0.1 is a local address. You need your computers dhcp given (or static address). It should like something like 192.168.something.something or 10.something.something.something. You can find this by opening a command prompt and typing "ipconfig".
Add this IP in Stanza as a catalog by hitting the "edit" button and selecting "add a book source" and then enter
http://192.168.something.something:8080 in the url, and put your computer's name for the name.
When it looks up your library using mdns (a weird protocol), it can sometimes take a while before it finds it due to network settings. So just add it as a catalog source. Everything will be much better. I do this on my own network, and set it up for everyone I introduce to Stanza/Calibre.