First of all, to see the domains you can run the command:
net view /domain
To see all the computers in your domain run the command:
net view /domain:"mshome"
To view the shared contents of a remote computer you can run the command:
net view \\computername

However what if you dont' want to be seen?
"Get a firewall"
Well maybe, but how bout this.

Right click "MyComputer" or go to "Properties". Click the "Computer Name" tab, then click "Change".

The workgroup text box at the bottom will show your current domain: (Ex: mshome, workgroup, i'mnot1337).

Time to make it " ". By this I mean hold "ALT" and type "255". This adds a blank space. Click ok and restart your computer. As far as I know, this blank workgroup will not be shown by "net view /domain"

cheers