if you want to register the domains
i'd say one of the three below
domainsite
namecheap
registerfly
These are the best domain registrars out there
I use several registrars too, and from them I can say NameCheap, Enom, and GoDaddy are very reliable.
i'll go for godaddy cheapest and most reliable domain registrar for me.
The one I use most is NameCheap.
I generally like any domain registrar that is a reseller of Enom that has Paypal payments enabled
NameCheap all the way, $7.99 domains (special discount) and great support...what more can you ask for!?
I like goaddy, paypal is accepted and their prices are very good.
Fabulous.com is the best for me!