Authorize.Net (https://www.authorize.net), a service of Lightbridge, is the preferred global payment-processing service for e-commerce, enabling merchants to process secure transactions in real time, 24 hours a day. Authorize.Net Payment Solutions process credit cards and electronic checks.
SpiritDomains/IARegistry has integrated with Authorize.Net API via Advanced Integration Method (AIM), that uses secure sockets layer (SSL) digital certificate technology to connect securely and directly to the Payment Gateway - achieving the highest security for the Internet connection between a merchant and the gateway.
Some of the useful links are listed below:
Find a Authorize.Net Reseller: https://www.authorizenet.com/reseller/directory.php
Signup for Authorize.Net Merchant Account: https://www.authorizenet.com/solutions/gettingstarted.php
Login to Authorize.Net Merchant Account: https://secure.authorize.net/
Support Center: https://www.authorizenet.com/support/