I recently discovered an excellent resource in the domaining business. Domcomp is a great website to compare the domain registration, transfer and renewal prices for domain names across 11 registrars and 600 plus extensions. They claim that the site is updated regularly and presents with the best possible prices. If you are into domaining and go for regular hand registrations, transfers and renewals, this tool is going to come handy!! Do try and share your experience about the same!!