I'm no licensing expert, unfortunately, but I know if you try to start up the Editor without a license, you get an error dialog. Within it, you should see a HOST ID, which is what you want to use for that field. For the Host name, it's whatever you want, just an identifier so you know who has which licenses.
I believe in 6.0 and above, you need a FlexNet license server, similar to the License Admin, but I'm not familiar with setting that up.