What domain extensions are you planning to register? i suppose that there are many places where you can reg various domains, but I'd recommend you to choose accredited domain Registrar.
I've used Enom for a long time and my only complaint is that when I bought the account my price was $6.95/yr but it's been increased slowly over the years. What is the acceptable going the rate for a .com now?
Oh, one thing I forgot to mention: Namecheap makes it easy to transfer ownership of domains which is a plus for me because I flip blog sites a lot.
this registrar not bad too internetbs.net you can get free whois for all TLD domains only about $7,xx/year