Reading

A good online source is Zytrax's Book on DNS.

Standard

A go to config for DNS might be:

acl "soho" {
       192.168/16;
       127/8;
};

options {
       listen-on port 53 { any; };
       listen-on-v6 port 53 { ::1; };
       directory       "/var/named";
       dump-file       "/var/named/data/cache_dump.db";
       statistics-file "/var/named/data/named_stats.txt";
       memstatistics-file "/var/named/data/named_mem_stats.txt";
       allow-query     { any; };
       recursion no;
       allow-update {none;};
};

logging {
       channel default_debug {
               file "data/named.run";
               severity dynamic;
               print-time true;
               print-severity true;
               print-category true;
       };
};

view "internal" {
       match-clients   { soho; };
       recursion       yes;
       allow-recursion { soho; };

       forward first;
       forwarders {
               // your parent name servers IP addresses
       };

       zone "office.soho" IN {
               type master;
               file "internal/office.soho.db";
               forwarders {};
               allow-update {
                       // your DHCP servers IP addresses
               };
       };
};

view "external" {
       match-clients { any; };

       zone "example.com" IN {
               type master;
               file "external/example.com.db";
       };
};

Actually this breaks two rules of domain naming:

1. soho. is not a valid top-level domain name
2. We don't own the domain example.com.

But, you know, we're filthy casuals so we don't care. So long as we are happy to be using an invalid top-level domain name and that we are shadowing someone else's domain then we're good to go.