Browsing, which is what allows Windows systems to see each other in a decentralized environment, is an extension to CIFS (the open implementation of SMB).
A new host announces itself by directing, via NetBIOS, a HostAnnouncement frame to DOMAIN(1d), where DOMAIN is the name of the host's domain or workgroup and (1d) is the Master Browser NetBIOS suffix. When using NetBIOS over IP, this announcement is a UDP broadcast to the local subnet.
When configuring Samba, make sure the browsable (or browseable) coniguration option is set to YES.
EDIT:
A few people have mentioned host configuration files. These are normally used for native IP and NetBIOS name resolution in the absence of DNS and WINS, respectively. (If present, they can also override DNS and WINS, depending on the configuration of the resolvers.)
For IP, use hosts. For NetBIOS over IP, use lmhosts. (Windows NT allows you to use native IP name resolution for NetBIOS applications as well as native IP applications. Windows 9x/Me does not.)
In Windows 9x/Me, these files are stored in %WINDIR%\System. In Windows NT/2000/XP/2003, these files are stored in %SystemRoot%\System32\drivers\etc.
Trev
