Who do I contact, and how do I figure out who has my reverse IP namespace?
I need to update the reverse lookup record, and potentially have it hosted on my own DNS server.
For what it's worth, we have a Class C.
Where did you get you IP address space from? You probably need to contact them.
If you are not sure, then lookup who owns your address space via whois, if the owner listed in whois isn't you or your ISP, then your ISP has probably got the address space from another organization, and you will need to have your ISP work with the organization that delegated the address space to them.