A. Registration Services    
Register domain names for yourself or your business.

Ampira - $20/yr.. domain registration, hosting, forwarding and unlimited email.
BudgetRegister.com - $15/yr.. services include url and email forwarding.
BulkRegister.com - $10-12/yr.. become a member and save on bulk registrations.
BuyDomains.com - $16/yr... domain registration and large reseller of pre-owned domains.
directNIC - $15/yr.. simple registration service.
Domain Name Systems - $10-15/yr.. specializing in quality customer service.
DomainIQ - $13.50/yr.. registration, expired domains, and appraisals.
DomainPeople - $35/yr.. register domains, email forwarding, and reseller programs.
Dotster.com - $15/yr.. simple registration service, bulk-registration available.
dotTV - $50/yr.. registering only .tv domains.
LowCostDomains.com - $24/yr... free domain parking, email, and forwarding.
NameBargain.com - $9/yr... there is a 5 name minimum for new users.
nameboy - $19/yr.. excellent name finder tool, plus appraisals, and more.
namecheap.com - $9/yr... cheap registration, with free domain services available.
namesecure - $25/yr.. registration, tools, resources, and more.
New.net - $25/yr.. registration of new TLD's, such as .shop, .kids, .mp3, and more.
Register.com - $35/yr.. manage, renew, email, sell, or buy multiple domains.
VeriSign - $35/yr.. formerly Network Solutions; complete domain services.
Yahoo! Domains - $35/yr.. includes free forwarding, and email account.

. Domain After-Market    
Brokers and resellers with quality domain names available from their current owners.

Afternic.com - mega-site.. very active auction and appraisal marketplace.
Domain Name Classifieds - classifieds.. classified listings, plus appraisal and registration.
DomainApex - auctions.. domain auction marketplace; appraisals available.
DomainSystems - mega-site.. known for it's elite domain showcase; registration available.
Great Domains - broker.. famous for its high-profile showcase, over a million domains.
Insane Domains - broker.. quality name showcases and auctions.
sedo - broker.. (europe) domains in many categories; featured showcase.
ShortDomains.com - reseller.. over 500 high-quality domain listings, prices available.
Website Names - broker.. over 1000 quality names, no prices listed.

. Appraisers    
Professional apparaisal services for domain names.

Accurate Domains - $10-70/name.. various appraisal packages available.
Domain Appraising - $7.50-10/name.. mix and match packages with top appraisers.
domainactions.com - $15-25/name.. appraisals in 1-5 days, multiple-name packages.

D. Resources   
News and insights into the domain name industry.

All WhoIs - who-is.. searches all databases for all domain extensions.
DN Resources - directory.. one of the best domain-related directories available.
DomainGuru.com - articles.. excellent guide for beginners and enthusiasts.
domainnamenews.com - news.. domain name news and resource listings.
DomainNotes.com - mega-site.. from internet.com; complete news and resources.
Domains illustrated - articles.. complete how-to guide, helpful articles, and headlines.
easyWHOIS - who-is.. simply who-is engine, plus a domain tracker.
ICANN - gov't.. organization responsible for regulating the domain industry.
igoldrush.com - mega-site.. guides and resources to buying, selling, and registering.
Mister Whizz - guide.. comparison charts on registration and domain hosting.
NameGuru.com - directory.. links to helpful resources in a dozen categories.
State of the Domain - analysis.. free subscription; monthly/quaterly domain industry reports.
Whois.net - who-is.. search by domain name or by keyword.
WIPO - artbitration.. the center to resolve domain name property conflicts.