Here are a few ways to use dig that I have found useful: To find the name servers for a TLD.
dig [TLD.] ns (relace TLD with com, net, org, us, etc.) To find the Authoritative Name Servers.
dig @[TLD Name Server] [domain] ns To find the DNS record on a specific server, like the authoritative server.
dig @[Server] [domain] [records:A MX C TXT NS SOA]