Specific instructions for requesting a DNS update from the following domain registrars:
BulkRegister
Domain Bank
Domain Discover
Dotster
Enom
GoDaddy
Network Solutions
Register.com
Tucows, Inc.

If you are unsure about which registar you registered your domain name with, go to a WHOIS, enter your domain name and click search. The company to contact should appear after "Registrar:" It's important to know that some registrars (i.e., Bulkregister.com and Enom.com) have resellers, so in some cases you may need to contact a reseller to have your domain's DNS information updated. To find the reseller in your domain registration record, scroll down a little further on the betterwhois output and look for "Registration Service Provided By:" and notice the contact information listed directly underneath.